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Browsing by discipline "Farmakologia"

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  • Kinnunen, Marja (2015)
    Histamine is a monoamine structured signal molecule, which takes part in many functions of living organisms. It was first found in brain approximately 70 years ago. Neuronal histamine regulates for example biological rhythms, energy metabolism and thermoregulation. In the 1980's, H3-receptor was recognized in the brain. Neuronal histamine regulates functions of other transmitters for example gamma-aminobutyric acid, glutamate, acetylcholine, noradrenaline and dopamine. Currently, the interactions of histamine and dopamine are not well characterized. Though, it is known that histaminergic fibers innerviate almost every dopaminergic area of the brain. There are also several H3-receptors in the striatum and in the limbic system. These brain areas are important for the rewarding effect of dopamine. The aim of the experimental part of this Master's thesis was to examine the location of histaminergic and dopaminergic nervous systems in mouse brain by using immunohistochemistry. Primary antibodies that were produced in rabbit (anti-histamine (HA)) and in mouse (anti-tyrosine hydroxylase (TH)), and secondary anti-rabbit and anti-mouse anti-bodies, that were produced in goat and conjugated with fluorophores, were used in the study. The samples were imaged with a confocal microscope. The primary aim was to find out, in which addiction related brain areas, histamine and dopamine cells and fibers are located and how they are situated in relation to each other. H3-receptor antagonists have been shown to decrease the consumption and rewarding effect of alcohol in animal models. Therefore, it was examined if non-imidazole structured H3-receptor antagonist also inhibits the rewarding effect of amphetamine, and if it decreases the locomotor activity induced by amphetamine. JNJ-39220675, a neutral antagonist of H3-receptor, and behavioral paradigm of conditioned place preference (CPP) were used in the experiment. CPP was also used to find out if D2-receptor agonist quinpirole cause reward or aversion. The effect of JNJ-39220675 on quinpirole's place preference and change in locomotor activity was also investigated. The interactions of these two pharmacological ligands were also examined in a separate locomotor activity experiment. C57BL/6J mice were used in all experiments. The results show that there are possible synaptic connections of histaminergic and dopaminergic system in substantia nigra, supramammillary nucleus, dorsomedial hypothalamic area and ventral periaqueductal grey area. Also, histaminergic nerve fibers innerviate to the dorsal striatum, which regulates motor functions, and to the ventral striatum, which is a part of the rewarding system of the brain. Hence, it is possible that histamine regulates the actions of dopa-mine in these brain areas. The behavioral experiments showed that JNJ-39220675 inhibits acutely increased locomotor activity caused by amphetamine, and decreases desensitation of decreased locomotor action caused by repeated dose of quinpirole. However, JNJ-39220675 did not have any effect on the rewarding effect of amphetamine, which causes strong sensitization. Also, JNJ-39220675 did not have an effect on quinpirole's aversive action. It remains to be seen, if H3-receptor is a potential target for new medicines in the treatment of different brain diseases and addiction in the future.
  • Larkiala, Jonna (2018)
    Obesity is a health problem linked to Western lifestyle and it is becoming more general. The complexity of regulation of eating makes it difficult to regulate body weight, when multiple neural networks and regions of brain have overlapping functions regarding to energy gain. Sufficient amount of energy is vital for individuals surviving in their living environment. Cholinergic messaging in brain is wide and for example nicotine is known for its appetite reducing effect. Anorexigenic proopiomelanocortin neurons mediate the effect of nicotine. In nucleus accumbens and central nucleus of amygdala extracellular levels of acetylcholine rise during meal, which promotes satiety. Satiety inhibits eating behavior between meals. Amygdala is a part of limbic system and in earlier knowledge it was associated only to regulation of memory, conditioning and fear. Nowadays importance of amygdala in eating behavior research is rising, but most of the studies focus on the effect of cue in regulation of eating. Cholinergic messaging is vigorous in the amygdala and is received from opposite areas of brain between basolateral and central amygdala and therefore this master’s thesis examined the effect of cholinergic messaging in amygdala on regulation of eating behavior. C57BL/6JRcc male mice were stereotaxically implanted with guide cannulas either in the basolateral complex of amygdala (n=10) or central nucleus (n=13). After recovering and habituation to automated pellet dispenser mice were treated with nicotinic and muscarinic receptor agonists and antagonists and eating behavior was recorded for six hours. Nicotine, administered to central and basolateral part of amygdala, lowered the number of pellets mice ate. In central nucleus effect was dose dependent. Mecamylamine had time related effect on eating behavior in basolateral amygdala, but dose dependent response was seen only in cumulative results. Oxotremorine was the only compound which created statistically significant interaction between time and dose. Result was seen in both groups. Scopolamine reduced eating behavior in central nucleus and dose dependency was seen. In basolateral complex scopolamine had time related effect, similar to mecamylamine. The results suggest that amygdala regulates eating behavior even without cue.
  • Volotinen, Katariina (2012)
    Kolinergiset α6*-nikotiinireseptorit ovat kiinnostavia, koska ne liittyvät mahdollisesti Parkinsonin tautiin ja nikotiiniriippuvuuteen. Ionikanavina toimivat nikotiinireseptorit ovat muodostuneet viidestä alayksiköstä, jotka esiintyvät erilaisina yhdistelminä. α6-alayksikköä sisältävät nikotiinireseptorit sijaitsevat presynaptisesti ja säätelevät dopamiinin vapautumista dopaminergisessä hermopäätteessä. α6*-nikotiinireseptorit ovat keskittyneet vain tietyille aivoalueille ja niitä esiintyy runsaasti dopaminergisissä hermosoluissa. α6*-nikotiinireseptoreita on erityisesti mesolimbisen ja nigrostriataalisen hermoradan dopaminergisissä hermosoluissa. Lisäksi niitä on paljon näkemiseen liittyvillä aivoalueilla. Nikotiini toimii asetyylikoliinin tavoin aktivoimalla α6*-nikotiinireseptoreita, mikä johtaa dopamiinin vapautumiseen hermopäätteessä. α6*-nikotiinireseptoreiden sijainnin, määrän ja toiminnan tutkimisessa on käytetty apuna muun muassa niille selektiivisiä antagonisteja, saalistavista merietanoista peräisin olevia α-konotoksiineja, erityisesti α-konotoksiini MII:ta. Nigrostriataalisella hermoradalla, joka ulottuu substantia nigrasta striatumiin, α6*-nikotiinireseptorit voivat vaikuttaa liikkeen säätelyyn. Nikotiini vapauttaa dopamiinia nigrostriataalisen hermoradan päätepisteessä, striatumissa, mikä voi lisätä liikeaktiivisuutta. Nikotiinilla on havaittu olevan hyödyllisiä vaikutuksia Parkinsonin taudin eläinmalleissa, mutta Parkinsonin tautipotilailla nikotiinihoidosta saadut tutkimustulokset ovat ristiriitaisia ja puutteellisia. α6*-nikotiinireseptoreille voitaisiin kehittää selektiivisiä agonisteja, joiden avulla lääkehoito voitaisiin kohdentaa paremmin ja vältyttäisiin mahdollisilta haittavaikutuksilta. Tupakanvieroitukseen tarvittaisiin lisää uusia selektiivisiä lääkehoitoja, joilla olisi hyvä hoitomyöntyvyys ja mahdollisimman vähän haittavaikutuksia. Mesolimbinen hermorata, joka ulottuu ventraaliselta tegmentaalialueelta nucleus accumbensiin, liittyy riippuvuuden syntyyn. Nikotiinin vaikutukset välittyvät VTA:n kautta nucleus accumbensiin, jossa vapautuu dopamiinia. Osa nikotiinin vaikutuksista välittyy myös presynaptisten α6*-nikotiinireseptorien kautta. Selektiivisistä α6*-nikotiinireseptoreiden antagonisteista voisi olla hyötyä nikotiiniriippuvuuden hoidossa, sillä niiden vaikutus vastaisi osittaisagonistin vaikutusta. α-konotoksiini PIA:n vaikutuksia nikotiinin aiheuttamaan dopamiinin vapautumiseen tutkittiin in vivo mikrodialyysimenetelmällä. α-konotoksiini PIA saalistavasta merietanasta eristetty selektiivinen α6*-nikotiinireseptoreiden antagonisti. Tutkimuksessa käytettiin vapaana liikkuvia urospuoleisia Wistar-rottia. Tutkimuksen kohteena olevat aivoalueet olivat striatum ja nucleus accumbens. Rotille asennettiin anestesiassa ohjauskanyyli joko striatumiin tai nucleus accum-bensiin stereotaktisen laitteen avulla. Mikrodialyysikokeessa koetinten tasapainotuksen jälkeen kerättiin perustason näytteet ja pistettiin saliini tai nomifensiini tai vaihdettiin Ringer-ruiskun tilalle α-konotoksiini PIA-ruisku. Puolen tunnin päästä pistettiin saliini tai nikotiini ja vaihdettiin Ringer-ruisku takaisin. Näytteitä kerättiin 15 minuutin välein yhteensä 5,5 tuntia. Lopuksi aivot otettiin talteen ja niistä tehtyjen aivoleikkeiden avulla tarkastettiin koetinten paikat. Mikrodialyysinäytteistä määritettiin HPLC-menetelmällä dopamiinin ja sen metaboliittien DO-PAC:n ja homovaniliinihapon sekä koejärjestelyssä oletettavasti muuttumattomana pysyvän 5-HIAA:n pitoisuudet. Koejärjestelyssä päätettiin käyttää tutkittavien aivoalueiden dopamiinipitoisuuden nostamiseen nomifensiinia, joka estää dopamiinin takaisinottoa hermopäätteissä. Käsittelyryhminä olivat saliini-saliini (n=striatum ja nucleus accumbens, 8+7), saliini-nomifensiini (n=8+4), saliini-nikotiini (n=3+4), nomifensiini-nikotiini (n=10+13) ja nomifensiini-nikotiini-α-konotoksiini PIA (n=8+5). Rottia jouduttiin hylkäämään eri syistä joko ennen mikrodialyysia, mikrodialyysin aikana tai sen jälkeen. Rottia hylättiin yhteensä 70 kpl. Tilastollisessa analyysissä tutkittujen käsittelyiden tai aivoalueiden välille ei saatu merkitseviä eroja, koska eläinten välinen hajonta oli liian suurta. Silmämääräisesti nomifensiini-nikotiinikäsittely nosti striatumin ja nucleus accumbensin dopamiinipitoisuuksia. α-konotoksiini PIA näytti estävän dopamiinin vapautumista striatumissa ja nucleus accumbensissa, mutta erot nomifensiini-nikotiinikäsittelyyn eivät olleet tilastollisesti merkitseviä. AUC-arvolla mitattuna α-konotoksiini PIA esti dopamiinin vapautumista striatumissa 39,6 % ja nucleus accumbensissa 31,3 %. Aivoalueiden välillä ei ollut tilastollisesti merkitseviä eroja.
  • Antila, Hanna (2012)
    Tissue plasminogen activator (tPA) is a serine protease that cleaves the inactive plasminogen to a broad-spectrum protease plasmin. Plasmin is involved in the degradation of blood clots by breaking down the fibrin network. In addition to it's role in the fibrinolytic system, tPA participates in the functions of the central nervous system. tPA is expressed in several brain areas and has been shown to be involved in neuronal plasticity. tPA's effects on brain plasticity are mediated in part via degradation of extracellular matrix proteins, but mainly via processing of brain-derived neurotrophic factor (BDNF). Plasmin cleaves pro-BDNF into BDNF that serves as primary endogenous ligand for TrkB neurotrophin receptor. TrkB signalling is strongly associated with the regulation of neuronal plasticity such as neurogenesis, synaptogenesis and long-term potentiation (LTP). On the contrary, pro-BDNF binds and activates p75 neurotrophin receptor that regulates many distinct, even opposite, effects on neuronal plasticity such as long-term depression and synapse refraction. Enhancement of brain plasticity is considered to be important for the therapeutic effects of antidepressant drugs and this is at least partially mediated via BDNF. Antidepressants activate TrkB receptors and increase BDNF protein levels in the rodent brain but the mechanism behind this remains obscure. Given that tPA is an important factor in the processing of BDNF, it is a possible mediator for antidepressants' neurotrophic effects. The effects of antidepressants on tPA activity have been previously studied only in the blood circulatory system. The aim of the experimental part of this Master's thesis was to examine the effects of antidepressant fluoxetine on tPA activity and protein levels in mouse hippocampus. Also the effects of fluoxetine on BDNF-TrkB signalling were studied. Fluoxetine was administered to mice acutely (30 mg/kg, i.p., 1 h) and chronically (0,08 mg/ml in drinking water, 3 weeks). tPA activity was studied using SDS-PAGE - and in situzymographies. TrkB activation, tPA and BDNF protein levels were measured using western blot. BDNF protein levels were also examined with ELISA method. No changes in tPA activity were found after acute fluoxetine treatment. In line with this result is the observation that also the BDNF levels remained unchanged. However, TrkB receptor activity was increased in fluoxetine treated mice. It seems possible that BDNF is not involved in the TrkB activation caused by acute fluoxetine treatment. Chronic fluoxetine treatment caused a significant increase in the BDNF protein levels compared to water-drinking control mice. This was not, however, associated with significant changes in TrkB activity. No changes in tPA activity were observed, which suggests that tPA is not involved in the increase of BDNF levels after chronic fluoxetine treatment. Interestingly, tPA antibody detected three distinct proteins in western blot of whose levels acute fluoxetine treatment regulated. However, more studies are needed to identify these proteins and to reveal the significance of such an effect of fluoxetine. According to this study, neither acute nor chronic fluoxetine treatment affects tPA activity in mouse hippocampus. However, environmental enrichment has been shown to enhance tPA activity and produce similar neurotrophic effects as chronic fluoxetine treatment. Therefore the result of this study concerning effect of chronic antidepressant treatment on tPA activity should be verified.
  • Ala-Kurikka, Tommi (2013)
    Laminins are a family of heterotrimeric glycoproteins found mainly in basement membranes. They interact with numerous other extracellular matrix components and cell surface receptors, including integrins and α-dystroglycan. Laminins play roles in myriad of functions including tissue morphogenesis, organogenesis, maintenance of tissue integrity and compartmentalization. In central nervous system laminins are involved in every major developmental stage from neural tube closure to synaptogenesis. Laminin expression in central nervous system decreases after maturation but has been found inducible by injury after trauma or disease. Since laminins are known to promote neurite outgrowth and neuronal survival, this has been proposed as a regenerative response to injury. Although the effects of endogenous laminin are clearly inadequate for repair, laminin based compounds could be powerful therapeutic agents. In previous in vivo studies KDI-tripeptide, a neurite outgrowth promoting fragment from γ1-laminin, has proved effective neuroprotective and regeneration promoting compound. Encouraged by these results I set out to test whether KDI would rescue midbrain dopaminergic neurons in unilateral 6-hydroxydopamine-induced rat model of Parkinson's disease. KDI (1-30µg) was injected to the striatum six hours prior to 6-hydroxydopamine. The severity of the lesion was then evaluated by measuring D-amphetamine induced rotation 2, 4 and 6 weeks postlesion and by assessing the number of neurons in substantia nigra pars compacta and optical density of striatum after tyrosine hydroxylase immunostaining at week seven. The only effective KDI dose studied was 3 µg. Compared to control it decreased Damphetamine induced rotational behaviour significantly at week four. KDI, however, failed to save tyrosine hydroxylase positive dopaminergic neurons in substantia nigra pars compacta or their axons in striatum. KDI might be usable in treating Parkinson's disease but it's mode of action doesn't appear to rely on protecting dopaminergic neurons or promoting the branching of their axons. KDI is known to inhibit ionotropic glutamate receptors and could therefore improve motor function by opposing striatal denervation induced overactivity of glutamatergic subthalamic nucleus neurons.
  • Nousiainen, Sini (2016)
    Parkinson's disease is a progressive neurodegenerative disease where dopaminergic neurons die in the substantia nigra pars compacta. Dopamine depletion induces typical parkinsonian motor symptoms which are treated by the golden standard medication levodopa and compounds enhancing the effect of levodopa. However in 4-6 years after the initiation of the chronic levodopa therapy abnormal involuntary movements (AIMs, also called levodopa-induced dyskinesia, LID) often develop and can notably worsen the quality of life. The most effective treatment for LID is deep brain stimulation (DBS), but as an invasive method its use is rare and not suitable for all patients. To date the only effective therapy for LID with marketing authorisation is amantadine. The disadvantage of amantadine is loss of efficacy which might appear less than a year after the initiation of medication. The pathophysiology of LID is a diverse phenomenon and includes dysfunctions in several different neurotransmitter systems both in the basal ganglia and in surrounding brain areas. The role of nicotinic acetylcholine receptors (nAChRs) in the pathophysiology of LID has been studied recently. Both nicotine and several nicotine-like agents have been shown to alleviate LID in preclinical studies and nicotine itself has been tested in a clinical phase II study as a potential LID medication. Of various different nAChR subtypes, the α7 receptor seems to be a potential option for future therapy of LID. It has been shown that α7 nAChR knock out mice display an increase in LID suggesting that this nicotinic receptor subtype has an inhibitory impact on the development of LID. Other studies have confirmed this view by showing that a selective α7 nAChR agonist (ABT-107) alleviates LID in primates and is neuroprotective for dopaminergic neurons in rats. Based on these observations, the aim of this study was to examine the effect of a novel α7 nAChR agonist (AZD0328) on LID in a 6-OHDA mouse model of Parkinson's disease. C57BL/6J female mice (n=17) were injected unilaterally 6-OHDA solution (3 µg) into the right medial forebrain bundle (MFB). Degeneration of dopaminergic neurons was detected two weeks after the 6-OHDA injection by measuring the motor performance in rotating rod with accelerated speed and with amphetamine-induced rotametry (2.5 mg/kg, i.p.). In the beginning of the chronic treatment, levodopa (4.5 mg/kg, s.c.) was administered twice daily for four days and then continued once daily (from Mon to Sun) to the end of the experiments. Levodopa treatment had been ongoing for 10 days before the first testing of drug effects. The pretreatment (AZD0328 0.06, 0.19, 1.9 mg/kg or 0.9 % saline, s.c.) was given 30 minutes before levodopa. The study was conducted using a within subject design so that each mouse received all four treatments on four test days during three weeks. Mice were videorecorded for 1 minute 20, 40, 60, 80 and 100 minutes after the levodopa injection was given. After the last recording day mice were killed under anesthesia via perfusion fixation and brains were collected for immunohistochemical staining to measure the extent of degeneration of dopaminergic neurons. 54 % of mice who survived from surgery (13/17) were dyskinetic (n=7). AZD0328 alleviated axial dyskinesia statistically significantly 40 minutes after levodopa injection but the statistical analysis did not reveal which of the doses was the most effective. The pretreatment with AZD0328 did not affect orolingual or forepaw dyskinesia. A potential mechanism of AZD0328 in alleviating LID might be the desensitization of α7 nAChRs which would happen only at very low doses. This means that LID are only attenuated when receptors are temporarily activated and then immediately gradually inactivated. The doses used in this study might have only activated the α7 nAChRs which might explain why no clear alleviation of LID was observed. On the other hand, the acute treatment may also be insufficient to develop desensitization. Additional studies are needed to investigate the effects of chronic administration of AZD0328 on LID in mice.
  • Korpi, Anna (2011)
    Heart failure is a complex and severe syndrome caused by different kinds of cardiovascular diseases. Pathophysiology of heart failure involves, for example, activation of sympathetic nervous system and the renin-angiotensin-aldosterone system (RAAS), insufficiently contracting left ventricle, cardiac remodeling, myocyte mishandling of Ca2+ and myocyte loss owing to apoptosis. Despite advances in the management of patients with heart failure, the mortality of patients with heart failure remains high. The use of classic inotropic agents is hampered by poor prognosis due to increase in [Ca2+]i, induction of arrhytmias and increase in the myocardial oxygen consumption. Levosimendan is an inotropic agent that has positive inotropic and anti-stunning effects mediated by the calcium sensitization of the contractile proteins and vasodilatory, anti-ischemic and cardioprotective effects mediated by opening of sarcolemmal and mitochondrial KATP channels. Levosimendan also inhibits cardiac PDE3 predominately at higher concentrations. Levosimendan is currently used only as 24-hour infusion to improve symptoms of acute decompensated heart failure. However, other promising indications have also been discovered. For example, chronic use of oral levosimendan improves survival and protects cardiovascular system in vivo. In the present study, the effects of oral levosimendan, valsartan and their combination use on survival, blood pressure and cardiac remodeling were examined in Dahl/Rapp rats on a high salt diet (8 %). Levosimendan improved the survival in Dahl/Rapp rats on a high-salt diet, although not statistically significantly when compared to control group. The drug combination prevented completely salt-induced cardiovascular mortality. The combination therapy also produced a blood pressure-dependent protection against hypertension-induced hypertrophy measured by heart weight-to-body weight ratio (HW/BW) and echocardiographic parameters. Interestingly, the combination use of levosimendan and valsartan had an additive antihypertensive effect in Dahl/Rapp rats. Levosimendan slightly improved systolic function. However, echocardiography revealed increased IVRT in Dahl/Rapp control rats when compared to control group on low salt diet (0,2 %) indicating impaired diastolic relaxation in Dahl/Rapp rats. In the present study, levosimendan, alone and in combination with valsartan, also corrected hypertension-induced diastolic dysfunction.
  • Rosenholm, Marko (2016)
    Pharmacologically induced neuronal plasticity holds unprecedented potential in treatment of several neurological disorders, such as depression. Several antidepressant drugs have been shown to induce neuronal plasticity by stimulating BDNF (brain-derived neurotrophic factor) receptor TrkB (tropomyosin receptor kinase B). Studies with rapid-acting antidepressant treatments suggest delta range slow wave EEG (electroencephalography) activity to function as a potential non-invasive biomarker for activation of TrkB-related neuroplastic signaling responses. A sedative GABAA-agonist THIP (gaboxadol) has been shown to induce slow wave EEG activity (SWA) and preliminary studies suggest it to activate TrkB signaling as well. The aim of the present study was to examine the potential connection between SWA, neuroplastic signaling responses and neuronal inhibition by utilizing EEG measurements and THIP administration in genetic and developmental mouse models. The pharmaco-EEG experiments showed acute THIP administration (6 mg/kg, i.p.) to increase SWA in wild-type but not in GABAA δ-subunit knockout mice. TrkB signaling responses from similar treatment groups showed a trend of increased TrkB-related protein phosphorylation in wild-type but not in GABAA δ-subunit knockout mice indicating a positive connection between SWA, neuronal inhibition and TrkB-related signaling response. Autophosphorylation response of TrkB and related proteins in mice of different age showed most TrkB phosphorylation in postnatal day 16 (P16) mouse pups, whereas phosphorylation response of CREB and p70S6k was the highest in postnatal day 8 (P8) mouse pups. Since SWA emerges during the second postnatal week in mice, the obtained result further supports the connection between SWA and TrkB signaling. Acute THIP administration caused no significant phosphorylation changes in P8 or P16 mouse pups. The results support the hypothesis of a positive connection between SWA, neuronal inhibition and TrkB-related signaling response. Further studies with different excitatory and inhibitory interventions are required to better understand the role of neuronal excitation and inhibition in TrkB signaling responses and corresponding EEG signatures.
  • Huynh, Thi Le Hang (2010)
    In the written part of my master -thesis I discuss about GDNF signalling and more specifically how the changes in the GDNF/GFRα1/Ret signaling affect the nigrostriatal dopaminergic neurons in different mutant mice. In the animal models of Parkinson's disease the neuroprotective and neurorestorative effects of exogenous GDNF are very clear which raises hope for use of GDNF in treatment of Parkinson's disease. In intact animals GDNF stimulates the function of nigrostriatal dopaminergic system. Revealing the role of GDNF/GFRα1/Ret signaling in development, maintenance and protection of nigrostriatal dopaminergic system will certainly help in search for treatment of neurodegeneration in Parkinson's disease. In knockout mouse models GDNF/GFRα1/Ret signaling is not crucial for prenatal nigrostriatal dopaminergic neuron development, but it has been shown that it plays an important role in the early postnatal development. Also, it was shown that reduced GDNF/GFRα1/Ret signaling compromises nigrotriatal dopaminergic system in heterozygous GDNF/GFRα1/Ret knockout mice. However the physiological roles of endogenous GDNF and its signalling in the nigrostriatal dopaminergic neurons are not very well understood. In the experimental part of my master -thesis I studied how reduced endogenous GDNF signaling affects the dopaminergic system after 6-OHDA induced neurotoxicity in the conventional heterozygous GDNF mice. Besides that I examined the effects of elevated endogenous GDNF on dopaminergic system of 7 days old so-called GDNF hypermorphs mice. The effects of reduced endogenous GFRα1 levels on dopaminergic system of 20 days old GFRα1 hypomorphs have also been studied. The obtained date showed that mice with the reduced levels of endogenous GDNF are not more susceptible to the 6-OHDA induced neurotoxicity than the wild type littermates. Elevated endogenous GDNF levels did not affect early postnatal development of the nigrostriatal dopaminergic system in GDNF hypermorphs mice as revealed by normal intensity of TH staining in striatum and normal number of TH-positive cells in the substantia nigra pars compacta. Reduced levels of endogenous GFRα1 levels did not affect monoamine levels in the striatum of GFRα1 hypomorph mice.
  • Anttila, Jenni (2013)
    Brain-derived neurotrophic factor (BDNF) and the receptor mediating its effects, neurotrophin receptor TrkB, seem to have a role in the pathophysiology and treatment of mood disorders such as depression and mania. BDNF is a neurotrophin that regulates the differentiation and survival of neurons and mediates neuronal plasticity. Lithium and valproate are mood stabilizing agents that are commonly used to treat mania but their mechanism of action is still unclear. However, both acute and chronic lithium treatment have been shown to activate TrkB receptor in the rodent anterior cingulate cortex. It has also been shown that chronic lithium and valproate treatment increase the amount of BDNF in the rodent brain. The aim of the experimental part of this master's thesis was to find out what are the effects of lithium and valproate on TrkB receptor activation and on the amount of intracellular BDNF protein levels in vitro on embryonic day 18 (E18) rat primary cortical neurons. In addition, the possible role of neuronal maturation was investigated by conducting the experiments with neuronal cultures aged 7 and 21 days in vitro. The research methods included two different types of enzyme linked immunosorbent assays (ELISA), phospho-Trk ELISA and BDNF ELISA. Western blot was used to confirm the results. Therapeutically relevant concentration of lithiumchloride and valproate blocked BDNFinduced TrkB receptor phosphorylation in immature neurons aged 7 days in vitro. The effect of valproate was detected only with ELISA. In contrast, therapeutically relevant concentration of valproate increased TrkB receptor phosphorylation in immature neurons after one hour treatment. Lithium and valproate did not regulate TrkB receptor phosphorylation in mature neurons aged 21 days in vitro. However, therapeutically relevant concentration of lithium increased BDNF protein content in mature neurons after 24 hours treatment. Therapeutically relevant concentration of valproate did not alter BDNF protein levels. In conclusion, neuronal maturation does have a role on the effects of lithium and valproate on TrkB receptor activation and regulation of BDNF protein levels. It is possible that lithium and valproate are harmful to immature neurons through blocking BDNF-induced TrkB receptor phosphorylation. Since therapeutically relevant concentration of lithium did not activate TrkB receptor as has been shown previously in vivo it seems that certain developmental processes are essential for lithium-induced TrkB receptor activation.
  • Kotonen, Anne (University of HelsinkiHelsingin yliopistoHelsingfors universitet, 1992)
    Tämän tutkimuksen tarkoituksena oli selvittää, onko Escherichia coli-bakteerin seerumiherkkyydellä yhteyttä akuutin mastiitintaudinkuvaan, tulehdusreaktion voimakkuuteen tai paranemistulokseen. Kirjallisuuskatsauksessa käsitellään mastiittia aiheuttavien koliformien bakteerien virulenssitekijöiden ja utareenpuolustusmekanismien vuorovaikutuksia. Hautjärven klinikan toimialueelta oli eristetty akuuteista mastiiteista bakteerikantoja (n=75), jotka oli alustavasti tunnistettu E. coli -bakteereiksi lähinnä pesäkemorfologian perusteella. Kannat identifioitiin käyttäen API 20 E -diagnostiikkakittiä. Bakteerien seerumiherkkyys määritettiin Bioscreen-analysaattorilla inkuboimalla Iso-Sensitest-liemeen suspensoituja bakteereita joko aktiivisessa seerumissa, inaktivoidussa (56 °C:ssa 30 min) seerumissa tai Hanksin balansoidussa suolaliuoksessa 20 h +37 °C:ssa . Kliinisten oireiden voimakkuus arvioitiin potilaskortteihin kirjattujen tietojen perusteella. Maidon NAGaasi-aktiivisuus mitattiin käyttäen MilkNAGase Testiä. Kannoista 68 identifioitiin E. coli -bakteeriksi. Näistä 36 (53 %)oli seerumiresistenttejä. Kannoista 24 (35 %) oli välimuotoisia ja 8 (12 %) seerumiherkkiä. Yleisoireiden vakavuuden perusteella 19 % tapauksista oli lieviä, 62 % kohtalaisen vakavia ja 19 % vakavia. Utareen turpoaminen oli voimakasta 55 %:ssa tapauksista ja erittäin voimakasta 45 %:ssa tapauksista. Maidon NAGaasi-aktiivisuuden keskiarvo - keskihajonta akuutissa vaiheessa oli 226 +- 171 U/ml ja seurantanäytteissä 113 +- 134 U/ml. E.coli -kantojen seerumiherkkyyden ja kliinisten oireiden voimakkuuden välillä ei ollut tilastollisesti merkitsevää eroa, ei myöskään seerumiherkkyyden ja akuutin vaiheen NAGaasi-aktiivisuuden välillä. Testattavia kantoja oli liian vähän, jotta seerumiherkkyyden ja seurantanäytteiden NAGaasin suhdetta olisi voinut käsitellä tilastollisesti.
  • Eskelinen, Ulla (University of HelsinkiHelsingin yliopistoHelsingfors universitet, 2001)
    Tutkimuksessa selvitettiin vasikoiden trakeobronkiaalihuuhtelunäytteissä esiintyviä MMP-2- ja MMP-9-tasoja sekä hengitysteiden Pasteurella-infektion yhteydessä MMP-aktiivisuuksissa tapahtuvia muutoksia. Tutkimusaineistoon kuului 11 hengitystietulehdusta sairastavaa vasikkaa sekä 6 tervettä vasikkaa sisältävä kontrolliryhmä. Vasikat valittiin ryhmiin yleistutkimuksen, verinäytetulosten ja trakeobronkiaalihuuhtelunesteen bakteriologisen tutkimuksen perusteella. Huuhtelunäytteiden gelatinolyyttisen aktiivisuuden määrittämiseen käytettiin gelatiinizymografiaa. Lisäksi gelatiinizymografialla tutkittiin, tuottaako erään tutkimusvasikan keuhkohuuhtelunäytteestä eristetty Pasteurella-bakteerikanta gelatinolyyttistä MMP:a. Kaikissa tutkituissa trakeobronkiaalihuuhtelunäytteissä havaittiin MMP-2- ja MMP-9-aktiivisuutta. Sairaiden ja terveiden vasikoiden MMP-tasojen eroja testattiin ei-parametrisella Mann-Whitney-testillä. Testattavat muuttujat olivat näytteen gelatinolyyttinen kokonaisaktiivisuus, kompleksimuodot, proMMP-9, aktiivinen MMP-9, proMMP-2 ja aktiivinen MMP-2 sekä aktiivisten MMP-muotojen prosentuaalinen osuus MMP:n kokonaistasosta. Ryhmien välillä havaittiin tilastollisesti merkitsevät eroavuudet (p<0,05) totaaliaktiivisuudessa sekä kompleksin ja MMP-2:n määrissä. Gelatinolyyttinen kokonaisaktiivisuus sekä aktiivisen MMP-2:n tasot olivat selvästi korkeampia sairailla kuin terveillä. Myös MMP-9-tasot olivat sairailla hieman korkeammat kuin terveillä, vaikka ero ei ollut tilastollisesti merkitsevä (p=0,056). Aktiivisten MMP-muotojen prosentuaalisissa osuuksissa sekä MMP-9:n ja MMP-2:n proentsyymimuotojen tasoissa ei ryhmien välillä havaittu tilastollisesti merkitseviä eroja. Pasteurella -kannan MMP-tuotannon selvittämiseksi tehty zymografia ei paljastanut bakteereista minkäänlaista gelatinolyyttistä aktiivisuutta. Pasteurellojen aiheuttama vasikoiden bronkopneumonia on kliinisesti ja taloudellisesti merkittävimpiä vasikoiden sairauksia. Taudille tyypillistä on laajojen keuhkokudoksen vaurioiden syntyminen, mikä vaikeuttaa infektiosta toipumista ja heikentää paranemisennustetta. Matriksimetalloproteinaasit ovat mm. tulehdussolujen tuottamia proteolyyttisiä entsyymejä, jotka hajottavat ekstrasellulaarista matriksia. Niiden proteolyyttisellä kapasiteetilla uskotaan olevan keskeinen rooli paitsi kudosten fysiologisessa uusiutumisessa myös erilaisten patologisten tilojen, kuten esimerkiksi eräiden hengitystiesairauksien, patogeneesissä sekä niihin liittyvien kudosvaurioiden synnyssä. Keuhkokudoksen matriksimetalloproteinaasi-aktiivisuuksien kohoaminen onkin osoittautunut hyväksi kudostuhon indikaattoriksi monissa hengityselinsairauksissa. Kirjallisuuskatsauksessa on käsitelty vasikoiden hengitystiesairauskompleksin esiintymistä, etiologiaa sekä oireita ja taudinkuvaa sekä Pasteurella-suvun tärkeimpien hengitystiepatogeenien, P. haemolytican ja P. multocidan, aiheuttamien hengitystietulehdusten erityispiirteitä ja bakteerien ominaisuuksia. Lisäksi käsitellään elimistön tulehdusvastetta ja kudosvaurioiden mekanismeja pasteurella- hengitystieinfektioissa sekä matriksimetalloproteinaasien (MMP) osuutta hengitystietulehduksen patogeneesissä.
  • Makkonen, Joanna (2016)
    Glutamatergisen hermosolutoiminnan häiriöt vaikuttavat olevan yhteydessä mielenterveys- ja mielialahäiriöihin. Metabotrooppiset glutamaattireseptorit ovat yksi mahdollinen kohde kun etsitään nykyisiä lääkkeitä tehokkaampia vaihtoehtoja näiden sairauksien hoitoon. Hiirten marmorikuulien hautaamiskokeen ajatellaan mittaavan hiirten ahdistuneisuutta ja pakko-oireisuutta, ja metabotrooppisen glutamaatti-2/3-reseptorin antagonisti LY-341495:llä on aikaisemmissa tutkimuksissa havaittu hautaamiskäyttäytymistä lievittäviä vaikutuksia tässä testissä. Tämän tutkimuksen tarkoituksena oli havainnoida LY-341495:n jo tunnettuja vaikutuksia hiirten käyttäytymiseen marmorikuulien hautaamiskokeessa ja selvittää, ovatko vaikutukset riippuvaisia mGlu3-reseptoreista. Lisäksi tutkimme LY-341495:n vaikutusta hiirten liikeaktiivisuuteen ja sitä, onko vaikutus samanlainen mGlu3R-poistogeenisillä hiirillä kuin villityyppi-hiirillä. Emme havainneet LY-341495:llä olevan vaikutusta villityyppi-hiirten marmorikuulien hautaamiskäyttäytymiseen tai liikeaktiivisuuteen. LY-341495 ei vaikuttanut myöskään mGlu3R-poistogeenisten hiirten marmorikuulien hautaamiskäyttäytymiseen. Havaitsimme kuitenkin LY-341495:llä olevan tilastollisesti merkittävä mGlu3R-poistogeenisten hiirten liikeaktiivisuutta lisäävä vaikutus. mGlu2-reseptorin toiminnan estyminen mGlu3-reseptorin suhteen poistogeenisillä hiirillä näyttää johtavan yliaktiivisuuteen. Pystyynnousu-aktiivisuuden lisääntymisestä ei kuitenkaan voi päätellä LY-341495:n vaikutusta mielialaan. Tuloksemme eivät tukeneet sitä, että LY-341495:n vaikutus villityyppi- tai mGlu3R-poistogeenisiin hiiriin olisi pakko-oireisuutta lievittävä.
  • Hölsö, Katariina (University of HelsinkiHelsingin yliopistoHelsingfors universitet, 2003)
    Tutkimuksia mikrobilääkkeiden käytöstä eläimillä eri indikaatioihin on tehty hyvin vähän. Mikrobilääkkeiden käyttö lemmikkieläimillä ei ole samalla tavalla lain kautta säädeltyä kuin tuotantoeläimille. Tästä johtuen uusia antimikrobisesti vaikuttavia lääkkeitä voidaan helposti alkaa käyttää lemmikkieläimille jopa ilman selkeää käyttöaihetta. Tutkimuksemme tavoitteena oli kerätä tietoa mihin indikaatioihin mikrobilääkkeitä käytetään Yliopistollisessa Eläinsairaalassa sekä verrata tietoa voimassa oleviin Maa- ja Metsätalousministeriön antibioottityöryhmän antamiin käyttösuosituksiin. Tietojen perusteella arvioimme onko mikrobilääkkeiden käyttö hallittua ja oikein suunnattua ja onko joitain osa-alueita joissa antibioottien käyttöä tulisi jollain tavalla ohjata. Keräsimme kuuden kuukauden ajalta, marraskuu 2000-huhtikuu 2001, tiedot kaikista eläinsairaalan pieneläinklinikalta määrätyistä mikrobilääkemääräyksistä. Tarkastelimme lähinnä potilaan saamaa antibioottia siihen indikaatioon mihin se oli määrätty sekä hoitojakson pituutta. Yli 20 % koirapotilaista (1324/5918) määrättiin peroraalista mikrobilääkettä. Yleisimmin käytettyjä olivat beetalaktaamit (49 %). Beetalaktaameista suosituimpia olivat ensimmäisen polven kefalosporiinit ja amoksisilliini-klavulaanihappo. Fluorokinolonien käyttö oli kaiken kaikkiaan melko vähäistä, niitä oli määrätty 4 % resepteistä. Eläinlääkärit määräsivät pyoderman hoitoon useimmiten laajakirjoisia beetalaktaameja, suositeltujen makrolidi-linkosamidien sijaan. Tämä poikkeaminen käyttösuosituksista on hyväksyttävää ottaen huomioon koiran pyodermassa usein esiintyvän Staphylococcus intermediuksen resistenssitilanteen. Akuutin virtsatieinfektion hoitoon käytettiin suositusten mukaisesti eniten trimetopriimi-sulfonamideja sekä amoksisilliini-klavulaanihappoa. Käyttöaiheita joissa mikrobilääkkeiden käyttö oli runsasta tai perusteetonta oli antibioottien käyttö kuurina leikkausten jälkeen kunnollisen antibioottiprofylaksian sijaan, akuuttien suolisto-oireiden hoito antibiootilla sekä mikrobilääkkeen määrääminen pienien haavojen ja traumojen hoitoon. Lääkemääräyksistä huomattava osa koski edellä mainittuja käyttöaiheita, joten erityisesti niiden kohdalla suosituksia olisi syytä painottaa. Koska Yliopistollinen Eläinsairaala toimii opetussairaalana, olisi tärkeää, että sillä on selkeä ja toimiva mikrobilääkepolitiikka.
  • Pöyhönen, Suvi (2017)
    Cortical stroke induces a chain of events that results in secondary injury in the ipsilateral thalamus. Inflammation is a key player in the delayed injury. Microglia, the resident innate immune cells of the brain, seem to have an important role in the initiation and maintenance of the inflammation. After infarct they are rapidly activated and start to proliferate and release proinflammatory cytokines. They may even phagocytose viable neurons, a phenomenon called "phagoptosis". Many studies, which have aimed at inhibition of the the detrimental function of microglia, suggest that inhibition of microglia might offer promising therapeutical targets. However, microglia are also involved in the resolution and the repair phase after infarct, which makes development of novel therapies challenging. The only approved treatment for ischemic stroke, a fibrinolytic agent, has a very narrow therapeutic time window. Thus, new treatments are urgently needed. Modulation of inflammation may offer a wider therapeutic time window. In this study, we investigated the effects of two potentially neurotrophic factors, CDNF (cerebral dopamine neurotrophic factor) and MANF (mesencephalic astrocyte-derived neurotrophic factor), as well as a specific vitronectin receptor blocker, cRGDfV, on the prevention of neuronal death in thalamus in a transient murine cortical stroke model. MANF and CDNF are proteins released during stress of the endoplasmic reticulum (ER). They have been shown to protect neurons during ER stress and to reduce the production of some proinflammatory mediators. The vitronectin receptor blocker has in vitro inhibited microglial phagoptosis. The treatments were administered as single injections to the thalamus 7 days after the stroke onset. CDNF and MANF alleviated functional deficits, but did not protect thalamic neurons from death or affect the accumulation of phagocytic microglia. cRGDfV neither enhanced functional outcome nor protected neurons from death. The mechanisms of action were not investigated. In addition, we investigated, whether the death of thalamic neurons in the cortical stroke results in sensitization to pain. Central post-stroke pain has been reported on stroke patients and it has been associated with the death or the disturbances in the function of thalamic neurons. However, in spite of significant reduction in the number of neurons in the ipsilateral thalamus and the increase in the accumulation of phagocytic microglia on day 30 after stroke, we did not observe any significant sensitization to pain caused by thermal or mechanical stimuli on days 3, 14 and 28 after stroke. In conclusion, transient ischemic cortical stroke doesn't seem to induce sensitization to pain. MANF and CDNF seem to alleviate functional deficiencies, but they do not protect thalamic neurons from delayed death.
  • Rantanen, Mimi (2016)
    The main purpose of this study was to participate in setting up the In situ hybridization for microRNA detection at the Department of Pharmacology. In situ hybridization (ISH) is an effective method for detection of molecules like DNA and RNA from paraffin fixed tissue sections. ISH provides information of expression and location of selected target molecules. Challenges of ISH for miRNA are the small size of the miRNAs and requirement of RNase free environment to prevent contamination. Micro-RNAs are single-stranded, noncoding, 19 to 25 nucleotides long RNAs, involved in post-transcriptional gene silencing. MiRNA-1 is known to be upregulated in ischemic heart muscle, which increases arrhythmias and apoptosis in heart. Adminstration of isoprenaline to Wistar rats induces similar conditions as acute myocardial infarction, which leads to rise in mir-1 levels. By in situ hybridization we were able to detect mir-1 from heart tissue and adjust suitable conditions for ISH.
  • Holkeri, Arttu (2016)
    Opioidien antinosiseptiivista vaikutusta on hyödynnetty pitkään kivun lievityksessä. Opioidien pitkäaikaiskäyttöä haittaa niille kehittyvä toleranssi. Uusimpien tutkimusten mukaan keskushermoston tukisoluilla, gliasoluilla, saattaa olla osuutensa toleranssin kehittymisessä. Eri opioidien välillä saattaa myös olla eroja toleranssin kehittymisessä. Tässä tutkimuksessa verrattiin kolmelle eri opioidille kehittyvää antinosiseptiivista toleranssia. Tutkimuksessa selvitettiin myös kroonisen opioidikäsittelyn aiheuttamaa gliasolujen aktivaatiota rottien aivoalueilla. Lisäksi tutkittiin lipopolysakkaridin vaikutusta morfiinitoleranssin kehittymiseen ja glia-aktivaatioon. Tutkimuksessa rotille muodostettiin opioiditoleranssit (morfiini, oksikodoni ja metadoni) 9 vuorokauden aikana. Lisäksi yhdelle ryhmälle annettiin lipopolysakkaridiesikäsittely. Opioidien aiheuttamaa antinosiseptiota mitattiin toleranssikäsittelyä ennen ja sen jälkeen. Rottien aivoista tehtiin mikroskooppileikkeet kolmesta eri aivoalueesta, joista tutkittiin mikroglia- sekä astrosyyttiaktivaatiota kolmella eri merkkiaineella (IBA1, OX-42 ja GFAP). Antinosiseptiokokeiden perusteella morfiinitoleranssi kehittyi nopeimmin ja oksikodonitoleranssi hitaimmin. Glia-aktivaatiossa ei nähty eroja eri opioidikäsittelyjen välillä.
  • Tulokas, Sari (2016)
    This study compared proliferation rate and expression of cardiac stem cell markers in one day seven days old mice hearts (1D and 7D). Primary antibodies Ki-67 and C-kit were used in immunohistochemistry and primers C-kit, GATA-4, Myh6, Sca-1 and Mesp1 were used in quantitative PCR. This study found a considerably higher proliferation rate and a higher number of C-kit+ stem cells in 1D than in 7D samples, but the difference was not statistically significant due to a small sample size. A significant difference in the expression of other studied markers was not found. These findings suggest that a decrease in proliferation rate and the number of C-kit+ stem cells coincide with the loss of regenerative potential. Therefore, it is possible that either, or both, of these changes are responsible for the closure of the regenerative window.
  • Nordström, Sabina (2010)
    Parkinson's disease is a chronic progressive neurodegenerative disorder, characterized by muscle rigidity, hypokinesia, tremors and bradykinesia. The cause of symptoms in Parkinson's disease is loss of dopaminergic nerve cells in the substantia nigra, which attenuates the nigrostriatal dopaminergic signaltransmission. Oxidative stress, mitochondrial dysfunction, protein misfolding and aggregation, inflammation, excitotoxicity, apoptosis and other routes for cell death, and loss of neurotrophic factors have shown to be mechanisms in the pathogenesis of Parkinson's disease. Microglia might have a double role in the pathogenesis of Parkinson's disease. Microglia stimulated by Į- synuclein does not only produce toxic factors such as certain cytokines and reactive oxygen and nitrogen species, which contribute to the neuronal cell death but also produce anti-inflammatory cytokines and neurotrophic factors, which can be neuroprotective. Deeper knowledge of the mechanisms underlying Parkinson's disease is needed for developing restorative medicines. Three different neurotrophic factor families are known to be important in the research of Parkinson's disease. The GDNF-family consists of glial cell line-derived neurotrophic factor (GDNF), neurturin (NRTN), artemin (ARTN) and persephin (PSPN). The neurotrophin-family consists of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophins NT3 and NT4/5. The most recently discovered family is the MANF-family, which consists of mesencephalic astrocyte-derived neurotrophic factor (MANF) and conserved dopamine neurotrophic factor (CDNF). In Parkinson's disease the neurotrophic factors could stop, slow or ideally even reverse the neurodegeneration in the dopaminergic system and decrease the functional decline of the neurons. Research has already shown that GDNF has both a neurorestorative and neuroprotective effect in animal models of Parkinson's disease. Clinical trials have however shown controversial results. The challenge with neurotrophic factors can be the administration to the brain through the blood-brain-barrier, sideeffects because of receptor binding in other organs or sites of the body and low diffusionrate. Research of both MANF and CDNF has shown promising neurorestorative and -protective results in vivo. Local diffusion of MANF has been shown to be better than of GDNF. In this Master's thesis research was done on whether MANF and CDNF have a neurorestorative effect on the dopaminergic nerve cells in mixed primary culture in vitro after 6-OHDA exposure. The aim of the study was to receive information about whether MANF and CDNF are as effective as GDNF at repairing celldamages caused by 6-OHDA in vitro in this experimental model. GDNF was used as a posivite control in this study. The results from this study suggest that MANF might have a neurorestorative effect, but this effect is much smaller than with the neurotrophic factor GDNF. The results show no neurorestorative effect with CDNF. Neither the dopamine uptake nor the tyrosine hydroxylase staining showed statistical significance.
  • Molari, Joonas (2018)
    Currently, there is an undeniable need for more effective treatments of depression. The efficacy of traditional antidepressant drugs becomes apparent after multiple weeks of treatment. New advancements in depression treatments have been made, as glutamatergic NMDA-receptor antagonist ketamine is seen to ameliorate symptoms rapidly, even only hours after drug administration. Understanding ketamine’s mechanism of action as an antidepressant could enable the development of more effective antidepressant drugs. The critical molecular level component in ketamine’s antidepressant effect is considered to be the activation of TrkB tyrosine receptor kinase B, which subsequently leads to the initiation of signaling pathways, which regulate synaptic plasticity. So far, it has not been examined; whether there is a difference in ketamine’s antidepressant effect based on the dosing-time of day. The aim of the present study was to find out if there is a variation between ketamine’s effect on synaptic plasticity and the circadian phase in which the drug is administered. Ketamine’s (200 or 50 mg/kg, i.p.) effects were studied in C57BL/6J–mice during light phase (mouse’s inactive phase) and dark phase (mouse’s active phase) of the day. The phase of the day didn’t affect the activity of TrkB signaling in its related parts (pTrkBTyr816, pGSK3βSer9, p-p70S6KTyr421/Ser424 and p-p44/42MAPKThr202/Tyr204) in prefrontal cortex samples which were analysed in Western blot assay. Ketamine increased dose-dependently the phosphorylation of GSK3βSer9 and p70S6KTyr421/Ser424 as well as decreased p-p44/42MAPKThr202/Tyr204 at 30 minutes after drug administration in both phases of the day. Ketamine (200 mg/kg, i.p.) also lowered the glucose concentration measured from the trunk blood. To examine the effect of hypoglycemia on the activity of TrkB signaling another experiment was conducted. The hypoglycemia induced by insulin detemir (6 IU/kg, i.p.) didn’t affect any measured protein phosphorylation at 60 minutes after drug administration. The results of this study support the notion of ketamine’s rapid and dosedependent induction of neuroplasticity. The possible role of hypoglycemia in ketamine's neuropharmacology should be investigated in future studies.