No abstract available.
Humans ; Serotonin*

There is no doubt that dopamine plays a critical role in the etiopathogenesis of schizophrenia. However, there appeared some limitations in explaining the complex phenomena of schizophrenia. Recent research data suggest that dysfunction in serotonergic system may be involved Before the dopamine hypothesis of schizophrenia became established, the interest in serotonin(5-ydroxytryptamine, 5-HT) as an etiological substrate of this illness occurred. Recently the importance and extent of 5-HT's involvement in the pathophysiology and mechanism of action of antipsychotic drug is actively investigated. In recent years, therapeutic success of clozapine and risperidones has increased attention on the interaction between the 5-HT and dopamine systems in schizophrenia. This led to the serotonin-dopamine for antipsychotic. The authors review the evidence for the role of 5-HT in schizophrenia and serotonin-dopamine interaction.
Clozapine ; Dopamine ; Schizophrenia* ; Serotonin*

The mirtazapine is a relatively new antidepressant that has noradrenergic and specific serotonin antagonist action(NaSSAs). This has been known as one of the most safest drugs because of its few side effects. Until now, there have been only one case report that mirtazapine causes a EPS side effect(restless leg syndrome). But the peculiar mechanism of this drug makes it impossible to explain the exact reasons why the mirtazapine could induce EPS symptoms. Authors obseved three cases of mirtazapine indeced akathisia. We could not explain the phenomenon the other way except akathisia. So here we presents the three case of mirtazapine induced akathisia and a few possible hypothesis of this phenomenon.
Leg ; Psychomotor Agitation* ; Serotonin

No abstract available.
Colon* ; Humans ; Serotonin*

Humans ; Serotonin ; Cardiovascular Diseases

Mosapride accelerates gastric emptying by acting on 5-hydroxytryptamine type 4 (5-HT₄) receptor and is frequently used in the treatment of gastrointestinal (GI) disorders requiring gastroprokinetic efficacy. We tested the effect of mosapride on 5-hydroxytryptamine type 3 (5-HT₃) receptor currents because the 5-HT₃ receptors are also known to be expressed in the GI system and have an important role in the regulation of GI functions. Using the whole-cell voltage clamp method, we compared the currents of the 5-HT₃ receptors when 5-HT was applied alone or was co-applied with mosapride in cultured NCB-20 cells known to express 5-HT₃ receptors. The 5-HT₃ receptor current amplitudes were inhibited by mosapride in a concentration-dependent manner. Mosapride blocked the peak currents evoked by the application of 5-HT in a competitive manner because the EC₅₀ shifted to the right without changing the maximal effect. The rise slopes of 5-HT₃ receptor currents were decreased by mosapride. Pre-application of mosapride before co-application, augmented the inhibitory effect of mosapride, which suggests a closed channel blocking mechanism. Mosapride also blocked the opened 5-HT₃ receptor because it inhibited the 5-HT₃ receptor current in the middle of the application of 5-HT. It accelerated desensitization of the 5-HT₃ receptor but did not change the recovery process from the receptor desensitization. There were no voltage-, or use-dependency in its blocking effects. These results suggest that mosapride inhibited the 5-HT₃ receptor through a competitive blocking mechanism probably by binding to the receptor in closed state, which could be involved in the pharmacological effects of mosapride to treat GI disorders.
Gastric Emptying ; Methods ; Serotonin

OBJECTIVE: Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), and noradrenergic and specific serotonergic antidepressant (NaSSA) are extensively used to treat the patients with depression. Although depressed patients are complaining of somatic pain as a complication of depression, there has not been any straight-forward comparative data of the effect of SSRIs, SNRIs, and NaSSA on pain. Therefore, in this study, we tried to figure out the effect of each drug i.e.SSRIs, SNRIs, and NaSSA, on pain by administrating each drug to three different groups of patient with depression. METHODS: We conducted a chart review of patients, who visited a university hospital. From January, 2010 to February, 2012, total 150 inpatients who had been diagnosed as major depression by Diagnostic and Statistical Manual of Mental Disorders-4th edition criteria, and administered any of three drugs [SSRIs (n=50), SNRIs (n=50), and NaSSA (n=50)] at least for fore weeks in the department of psychiatry in Chung-Ang University Hospital, were enrolled for this study. We compared and analyzed depressive symptoms and pain between three groups. Depressive symptoms and pain were evaluated by Korean version of the Hamilton Depression Rating Scale and visual analogue scale at baseline and fore weeks later. RESULTS: There was no difference in the age, gender, severity of depression and pain among three groups. However, there was difference in 50% depressive symptomatic improvement rate in the following four weeks among three groups. The number of patient found to achieve 50% symptomatic improvement in SSRIs, SNRIs, and NaSSA group was 17 (34%), 20 (40%), and 34 (54%) in each group, respectively, indicating significantly higher improvement rate in NaSSA compared to SSRIs. During four weeks of administration period, significant difference in 50% pain improvement rate was observed among three groups. The number of patient found to achieve 50% pain improvement in SSRIs, SNRIs, and NaSSA group was 14 (28%), 20 (40%), and 27 (54%) in each group, respectively, showing twice higher pain improvement rate in NaSSA compared to SSRIs. CONCLUSION: This result indicates better efficacy of NaSSA on pain improvement compared to SSRIs, and SNRIs in depressed patients. Although the effect of pain improvement has been mainly focused on SNRIs, result from this study suggests the need for further research and validation on the effect of NaSSA for pain control.
Depression ; Humans ; Inpatients ; Nociceptive Pain ; Norepinephrine ; Serotonin ; Serotonin Uptake Inhibitors

No abstract available.
Animals ; Clomipramine* ; Preoptic Area* ; Rats* ; Serotonin Uptake Inhibitors* ; Serotonin*

Serotonin is one of the most important neurotransmitters involved in the pathophysiology of depressive illness. The assessment of alteration of cerebral serotonin has been still controversial but interesting topic to study. Recently, increasing evidence has accumulated that the N100 amplitude slope reflects cerebral serotonin activity and treatment response of selective serotonin reuptake inhibitors (SSRIs). We report on two patients who showed abrupt mood changes and side effects after taking SSRI antidepressants. In both patients, aberrantly high N100 amplitude slopes were observed. Our cases suggest that the N100 amplitude slope may be a reliable indicator for predicting manic conversion and side effects in the SSRI treatment of depressive patients. Controlled studies are necessary to confirm whether a high N100 amplitude slope is a useful indicator of SSRI supersensitivity.
Antidepressive Agents ; Depression ; Humans ; Neurotransmitter Agents ; Serotonin ; Serotonin Uptake Inhibitors

Melittin-induced tonic pain model is characterized by local inflammation, edema, spontaneous flinchings, and sustained mechanical hypersensitivity. These nociceptive responses are mediated through selective activation of capsaicin-sensitive primary afferent fibers by melittin. The present study was undertaken to elucidate the role of peripheral 5-hydroxytryptamine (5-HT) receptors in the melittin-induced nociceptive responses. Changes in mechanical threshold, flinching behaviors and paw thickness were measured in rat intraplantarly injected with melittin (40microgram/paw) alone or treated together with melittin and 5-HT receptor antagonists. WAY-100635 (100microgram & 200microgram/paw), isamoltane hemifumarate (100microgram & 200microgram/paw), methysergide maleate (60microgram, 120microgram & 200microgram/paw) and ICS-205,930 (100microgram & 200microgram/paw) were intraplantarly injected 20 min before melittin injection. All 5-HT receptor antagonists tested in this experiment significantly attenuated the ability of melittin to reduce mechanical threshold and to induce flinching behaviors. 5-HT receptor antagonists, except ICS-205,930, had mild inhibitory effect on melittin-induced edema. These experimental findings suggest that multiple peripheral 5-HT receptors are involved in the melittin-induced nociceptive responses.
Animals ; Edema ; Hypersensitivity ; Inflammation ; Melitten ; Methysergide ; Rats* ; Receptors, Serotonin ; Serotonin*