The 5-HT1A receptors: from molecular biology to neuropsychiatric symptoms

Abstract

Among the multiple serotonin receptors identified to date, the 5-hydroxytryptamine (5-HT) 1A subtype is among the best known because selective ligands have been available for more than 15 years. Radioactive derivatives of these ligands make it possible to demonstrate the presence of 5-HT1A binding sites mainly in the limbic areas and in the raphe nuclei in the brain, where they correspond to post-synaptic receptors and pre-synaptic autoreceptors respectively. On stimulation of 5-HT1A autoreceptors, they regulate serotonin release in the distal regions of the neuron by inhibitory firing activity. In this way, they help to maintain the serotonin in the terminal regions at physiological levels, which favors correct neuronal functioning.

This review article summarizes key data on localization, study technique, molecular biology, signal transduction, differential functional properties of pre-synaptic versus post-synaptic 5-HT1A receptors, and behavioral effects and clinical correlates of their activation, especially cognitive and emotional responses. Mention is made about the role of these receptors in the neurogenesis process of certain brain areas and of the possible clinical and therapeutic implications of these processes.