5-hydroxytryptamine turnover

The main effects of BZs occur via positive allosteric modulation. The BZs and GABA bind to separate sites on the GABAa receptor complex. When a BZ occupies the BZ receptor, GABA s ability to open the chloride channels increases. With greater opening of the chloride channel, cellular excitability decreases (Ballenger, 1995). The final result of this decreased cellular excitability is widespread because of the extensive inhibitory role of GABA in the CNS. As a result, BZs may alter the turnover of neurotransmitters such as norepinephrine and serotonin (5-hydroxytryptamine [5-HT]). 

Okuda C., Saito A., Miyazaki M., and Kuriyama K. (1986) Alteration of the turnover of dopamine and 5-hydroxytryptamine in rat brain associated with hypothermia. Pharmacol. Biochem. Behav. 24, 79-83. 

Indolealkylamines. GC-MS methods applied in studies of the biochemical pharmacology of indoleamines parallel work on the catecholamines. SIM assays for serotonin (5-hydroxytryptamine), 5-methoxytryptamine, JV-acetylserotonin and melatonin (5-methoxy-N-acetyltryptamine) in rat pineal and brain tissue have been described [453,469]. Pentafluoro-propionyl derivatives and structural homologue standardisation were employed with detection limits in the subpicomole range. Estimation of central indoleamine turnover in man currently depends upon metabolite determination in CSF. Ion monitoring determination of indole-3-acetic acid [454] a metabolite of tryptamine, and isotope dilution assays for 5-hydroxyindoleacetic acid (5-HIAA) [455,458] have been reported. Serotonin is converted by central monoamine oxidase to 5-HIAA and the measurement of this metabolite, formerly by fluorimetry, is of interest in patients with CNS disorders [470]. GC-MS has also contributed to the identification of N,N-dimethyltryptamine in vitro [471] and isotope dilution technique has been applied to the measurement of this metabolite in control subjects and in psychiatric patients [472]. 

The synthesis rate and turnover time of 5-hydroxytryptamine in brains of rats treated chronically with morphine... 

Bennett, G. W., Marsden, C. A., Sharp, T., and Stolz, J. F., 1981a, Concomitant determination of endogenous release of dopamine, noradrenaline, 5-hydroxytryptamine, and thyrotrophin-releasing hormone (TRH) from rat brain slices and synaptosomes, in Central Neurotransmitter Turnover (C. J. Pycock and P. V. Taberner, eds.), pp. 183-189, Croom-Helm, London. 

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