Nervous system, central hydroxy tryptamine

Hydroxy tryptamine, or serotonin, is a neurotransmitter in the central nervous system (CNS). The nerve-cell bodies of the major serotoninergic neurones are in the midline raphe nuclei of the rostral pons, and ascending fibers innervate the basal ganglia, hypothalamus, thalamus, hippocampus, limbic forebrain, and areas of the cerebral cortex. The serotoninergic system plays an important role in the control of mood and behavior, motor activity, hunger, thermoregulation, sleep, certain hallucinatory states, and some neuro-endocrine mechanisms. 

Dumuis A, Bouhelal R, Sebben M, Cory R, Bockaert J. A nonclassical 5-hydroxy-tryptamine receptor positively coupled with adenylate cyclase in the central nervous system. Mol Pharmacol 1988 34 880-887. 

LSD acts on several sites in the central nervous system. It is a nonselective serotonin, or 5-hydroxy-tryptamine (5-HT) agonist on both presynaptic and postsynaptic receptor sites. The 5-HT2a receptor agonism is implicated in the modulation of hallucinations. In addition to the role of serotonin in causing hallucinations, other neurotransmitters, including glutamate and Di and D2 dopamine receptors, are implicated yet, their role remains elusive. 

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