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

Antidepressive Agents/therapeutic use* ; Serotonin ; Serotonin Plasma Membrane Transport Proteins

Selective serotonin reuptake inhibitors (SSRIs) are currently the treatment of choice in depression and constitute major portion of prescription in depressive patients. The role of serotonin receptors in bone is emerging, raising certain questions regarding the effect of blockade of serotonin reuptake in the bone metabolism. Clinical studies have reported an association of SSRI antidepressants which with increase in fracture and decrease in bone mineral density. This review focus on recent evidence that evaluate the association of SSRIs with the risk of fracture and bone mineral density and also the probable mechanisms that might be involved in such effects.
Antidepressive Agents ; Bone Density ; Depression ; Humans ; Metabolism ; Prescriptions ; Receptors, Serotonin ; Serotonin Uptake Inhibitors* ; Serotonin*

Here we report a case of serotonin syndrome caused by fluoxetine 20 mg and duloxetine 60 mg independently eight week apart. A 65-year old man developed fever, agitation and change of mental status after two weeks treatment with 20 mg of fluoxetine for depressive disorder. He was diagnosed unknown fever origin and discharged when fever subsided as antidepressant stopped. Eight weeks later he was prescribed 60 mg of duloxetine for the treatment of depressed mood. After 18 days on duloxetine he developed fever, agitation, myoclonus and change in mental status again. He improved rapidly after discontinuation of offending drug with supportive care. Despite serotonin syndrome is usually caused by poly-pharmacy of serotonergic drugs, this case shows unusual serotonin syndrome developed by therapeutic dose of two drugs of different classes independently.
Depressive Disorder ; Dihydroergotamine ; Fever ; Fluoxetine ; Humans ; Myoclonus ; Serotonin ; Serotonin Agents ; Serotonin Syndrome ; Thiophenes ; Duloxetine Hydrochloride

The serotonin has been known to play important roles in pathology of the mood disorders. We summerize the evidences of serotonin in pathology of the mood disorders in a view of neuroanatomical and neurochemical aspects. Nowaday, the selective serotonin reuptake inhibitors(SSRIs)may be practically the first line of antidepressants with traditional tricyclic antidepressants(TCAs. Authors review the role of serotonin in the treatment of the mood disorders, in a view of the general considerations in selecting antidepressants, pharmacology, therapeutic, indications, side effects, doses of medication, drug-discontinuation syndrome, drug-to-drug interactions, and special therapeutic situations.
Antidepressive Agents ; Mood Disorders* ; Pathology* ; Pharmacology ; Serotonin*

Dextromethorphan and chlorpeniramine are common ingredients of over-the-counter (OTC) cough pills. They are known to be safe when used alone, however, combination with other serotonergic drugs or use of an overdose can cause serotonergic toxicity. We report on a 43-year-old male and a 57-year-old female who ingested an overdose of antitussive drugs containing dextromethorphan and chlorpeniramine. They commonly presented with altered mentality and hyperreflexia on both upper and lower extremities. After conservative therapies, they were discharged with alert mentality. These cases are meaningful in that there are few cases of serotonin syndrome with an overdose of a combination of dextromethorphan and chlorpeniramine. Careful use with medication counseling for OTC cough pills is needed in order to prevent overdose of these ingredients.
Adult ; Antitussive Agents ; Cough ; Counseling ; Dextromethorphan ; Female ; Humans ; Lower Extremity ; Male ; Middle Aged ; Reflex, Abnormal ; Serotonin ; Serotonin Agents ; Serotonin Syndrome

Many neurotransmitters other than dopamine, such as serotonin, glutamate, etc, have been implicated in the pathophysiology of schizophrenia. The atypicality of new antipsychotics has been attributed to the relatively more potent 5-HT2A receptor antagonism compared to D2 receptor blocking action. However, dopamine still seems to be a cornerstone in terms of the pathophysiology of schizophrenia and mode of action of antipsychotics. Therefore, we reviewed all the relevant papers about the dopamine hypotheses for schizophrenia and reclassified into 3categories: 1) Regional classification of dopamine hypothesis ; 2) Dopamine gating (filtering) hypothesis ; and 3) Time-course classification of dopamine hypotheis. How they are developed and the implications of each hypothesis will be described in detail. In the future, dopamine hypothesis at molecular or cellular levels will be investigated more extensively though its current status is very primitive.
Antipsychotic Agents ; Classification ; Dopamine* ; Glutamic Acid ; Neurotransmitter Agents ; Receptor, Serotonin, 5-HT2A ; Schizophrenia* ; Serotonin

The aim of this study was to investigate the role of the 5-HT receptors in acetylcholine (ACh) release from the striatum. Slices from the rat striatum and synaptosomes were incubated with [3H]-choline and the release of the labelled products was evoked by electrical (3 Hz, 2 ms, 5 V/cm, rectangular pulses, 2 min) and potassium-stimulation (25 mM), respectively, and the influence of various serotonergic drugs on the evoked tritium outflows was investigated. Serotonin decreased the electrically-evoked ACh release in striatum in a concentration-dependent manner without the change of basal release. In hippocampal and entorhinal cortical slices, serotonin did not affect the evoked and basal release of ACh, but, at large dose (30 microM) decreased the evoked ACh release in hippocampus. 2,5-Dimethoxy-4-iodoamphetamine (DOI), a specific 5-HT 2A/2C agonist, decreased evoked ACh release in the striatum. CGS-12066A (5-HT 1B agonist), m-chlorophenyl-biguanide (5-HT 3 agonist) and 5-[(dimethyl -amino)methyl]-3-(1-methyl-1H-indol-3-yl)-1,2,4-oxadiazole (5-HT 3 antagonist) did not affect the evoked and basal ACh release in all tissues. Ritanserin, a specific 5-HT 2A/2C antagonist, blocked the inhibitory effects of serotonin and DOI, whereas, ketanserin, an another type of specific 5-HT 2A/2C antagonist did not affect the inhibitory effects of serotonin and DOI. In striatal synaptosomal preparation, serotonin and DOI did not affect the K +-evoked ACh release. These findings suggest that ritanserin-sensitive 5-HT 2A/2C receptors located in the soma and/or axons of the striatal cholinergic neurons play a important role in ACh release.
Acetylcholine* ; Animals ; Axons ; Carisoprodol ; Cholinergic Neurons ; Hippocampus ; Ketanserin ; Rats* ; Receptors, Serotonin* ; Ritanserin ; Serotonin Agents ; Serotonin* ; Synaptosomes ; Tritium

Major depression is a common mental illness, associated with high morbidity and mortality. Antidepressants have been the first-line therapies due to their confirmed efficacy, however, considering high rate of poor treatment response to these therapies, distressing side effects, and delayed onset of their efficacy, there has been much effort to find alternative treatments for major depression. Recently, evidence regarding disturbed circadian rhythms involved in the pathophysiology of major depression has emerged, the interest on this area has been increasing. Agomelatine is an emerging antidepressant, with a unique profile of selective antagonist at serotonin 2C (5-HT2C) receptors and melatonin receptor agonist. Previous studies have shown its superior efficacy over placebo in treating major depression. Previous trials have shown comparable antidepressant efficacy of agomelatine compared to other standard antidepressants including venlafaxine, sertraline, and fluoxetine. Regarding safety profile of agomelatine, it seems to be not associated with sexual dysfunction and it has less potential for serotonin syndrome or discontinuation syndrome than standard antidepressants including selective serotonin reuptake inhibitors. Considering favorable results on the efficacy and safety of agomelatine in treating depression, it could be a good, safe treatment alternative in the treatment of depression.
Antidepressive Agents ; Circadian Rhythm ; Depression ; Fluoxetine ; Mortality ; Receptors, Melatonin ; Serotonin ; Serotonin Syndrome ; Serotonin Uptake Inhibitors ; Sertraline ; Venlafaxine Hydrochloride

Most serotonin is found outside the central nervous system and functions much more than a neurotransmitter. Peripheral serotonin is produced by enterochromaffin cells in the gastrointestinal tract and secreted into blood. Serotonin, as a circulating amine, takes part in numerous biological processes including cardiovascular function, bowel motility, glucose metabolism and skeletal change. Serotonin signaling is regulated by serotonin receptors and serotonin transporters in multiple body organs. The drugs that manipulate the serotonergic system have been developed and used for the treatment of many systemic diseases. The richness of serotonergic modulation in the whole body provide both a pharmacologic opportunity and challenge.
Biological Processes ; Central Nervous System ; Enterochromaffin Cells ; Gastrointestinal Tract ; Glucose ; Neurotransmitter Agents ; Receptors, Serotonin ; Serotonin