Role of serotonin

Meltzer HY (1999) The role of serotonin in antipsychotic drug action. Neuropsychopharmacology 21 106S—115S... 

Di Matteo V., Cacchio M., Di Giulio C., Esposito E. (2002). Role of serotonin (2C) receptors in the control of brain dopaminergic function. Pharmacol. Biochem. Behav. 71, 727-34. 

Although many questions remain about the complicated role of serotonin and its receptors in regulating sleep and waking, recent neurochemical, electrophysiological, and neuropharmacological studies have revealed much detailed information about this process. 

Roth BL, Meltzer HY. The role of serotonin in schizophrenia. Raven Press,... 

Meltzer HY. Role of serotonin in the action of atypical antipsychotic drugs. Clin Neurosci 1995 3(2) 64—75. 

Mundo E, Walker M, Cate T, Macciar-di F, Kennedy JL. The role of serotonin transporter protein gene in antidepressant-induced mania in bipolar disorder preliminary findings. Arch Gen Psychiatry 2001 58 539-544. 

Results of studies on the role of serotonin-in the action of LSD, which were conducted on human subjects, may be more easily interpreted because they directly examined the hallucinogenic effects of LSD. Prior depletion of brain serotonin with reserpine accentuated the effects of LSD (34,71). As described above, prior treatment with a MAOI attenuated the effects of LSD (38,70) and... 

Browne, R. G. (1978) The role of serotonin in the discriminative stimulus properties of mescaline. In Drug Discrimination and Stale Dependent Learning, edited by B. T. Ho, D. W. Richards, and D. L. Chute, pp. 79-101. Academic Press, New York. 

The second theory is that some atypicals work by balancing dopamine blockade with serotonin receptor blockade. We know that one of the roles of serotonin is to attenuate (or lessen) dopamine activity. Blocking serotonin action therefore may release just enough dopamine activity in the nigrostriatal pathway to avoid EPS without interfering with the antipsychotic effects in the mesolimbic area. 

The role of serotonin (5-hydroxytryptamine, 5-HT) has also been extensively studied in depressed patients. Whereas the overall psycho-physiological effects of noradrenaline in the CNS appear to be linked to drive and motivation, 5-HT is primarily involved in the expression of mood. It is not surprising therefore to find that the serotonergic system is abnormal in depression. This is indicated by a reduction in the main 5-HT metabolite, 5-hydroxy indole acetic acid (5-HIAA), in the cerebrospinal fluid of severely depressed patients and a reduction in 5-HT and 5-HIAA in the limbic regions of the brain of suicide victims. The 5-HT receptor function also appears to be abnormal in depression. This is indicated by an increase in the density of cortical 5-HT2a receptors in the brains of suicide victims and also on the platelet membrane of depressed patients. Platelets may be considered as accessible models of the nerve terminal. 

In addition to their proven efficacy in the treatment of all types of depression, the SSRIs have been shown to be the drugs of choice in the treatment of panic disorder, obsessive-compulsive disorder, bulimia nervosa, and as an adjunct to the treatment of alcohol withdrawal and relapse prevention, premenstrual dysphoric disorder and post-traumatic stress disorder. The usefulness of these drugs in treating such a diverse group of disorders reflects the primary role of serotonin in the regulation of sleep, mood, impulsivity and food intake. 

Selective serotonin reuptake inhibitors have not been well studied in patients with chronic pain, nor has the role of serotonin been elucidated. However some clinical experience suggests that the perception of pain is diminished with selective serotonin reuptake inhibitors. 

Gammie SC, Nelson RJ (1999) Maternal aggression is reduced in neuronal nitric oxide synthase-deficient mice. J Neurosci 19 8027-8035 Caspar P, Cases O, Maroteaux L (2003) The developmental role of serotonin news from mouse molecular genetics. Nat Rev Neurosci 4 1002-1012 Gobbi G, Murphy DL, Lesch K, Blier P (2001) Modifications of the serotonergic system in mice lacking serotonin transporters an in vivo electrophysiological study. J Pharmacol Exp Ther 296 987-995... 

The biology of the monoamines is described in detail elsewhere. In simple terms, they facilitate transmission in neural pathways that originate in nuclei of the brainstem and have descending projections to the autonomic nervous system and widespread ascending projections to sites in the limbic system and cortex. These pathways modulate many aspects of behavioural function as well as anxiety responses. Of the three monoamines, the role of serotonin in anxiety is best understood, but the picture is complex as increased serotonergic activity may be anxiogenic or anxiolytic depending on the site of action (Bell and Nutt 1998). 

Owens MJ and Nemeroff CB. (1994). Role of serotonin in the pathophysiology of depression focus on the serotonin transporter. Clin Chem 40 288-295. 

Adding lithium. Coadministration of lithium is a proven method for enhancing the thymoleptic action of antidepressants in patients with depression (Heninger et al. 1983). Lithium has been hypothesized to potentiate antidepressant-induced increases in serotonin neurotransmission by enhancing presynaptic serotonin release in some brain regions (Blier and de Montigny 1992]. The success of lithium augmentation in depression and the hypothesized role of serotonin in OCD has prompted studies of the anti-OC efficacy of this approach. 

Finally, a study of patients with anxiety and their response to treatment with the benzodiazepines may offer further clues as to the role of serotonin and cognition. The benzodiazepines are known to influence serotonin systems, albeit in a complex manner [see Richards et al. 1991). 

Briley M, Chopin P, Moret C The role of serotonin in anxiety behavioral approaches, in New Concepts in Anxiety. Edited by Briley M, File SE. London, Macmillan, 1991, pp 56-73... 

Cervo L, Rossi C, Samanin R The role of serotonin and dopamine in brain in the antidepressant-like effect of clonidine in the forced swimming test. Neuropharmacology 31 331-335, 1992... 

Husain MM, Lewis SF, Thornton WL Maintenance ECT for refractory obsessive-compulsive disorder (letter). Am J Psychiatry 150 1899-1900, 1993 Hwang EC, Van Woert MH Antimyoclonic action of clonazepam the role of serotonin. Eur J Pharmacol 60 31-40, 1979... 

Ohouha DC, Hyde TM, Kleinman JE The role of serotonin in schizophrenia an overview of the nomenclature, distribution and alterations of serotonin receptors in the central nervous system. Psychopharmacology 112 S5-S15, 1993... 

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