Peripheral Serotonergic Mechanisms in Health and Disease

Abstract

Serotonin (5-hydroxytryptamine; 5HT) is found in the central nervous system, which contains serotonergic neurons, enterochromaffin cells in the intestine and platelets.^1–3 Receptors for serotonin have been found in various tissues including the central nervous system, gastrointestinal tract , blood vessels, blood platelets and autonomic nerve endings.⁴ 5-hydroxytryptamine is believed to play a role in physiology and pathophysiology of mammals. One of its most likely physiological roles is to aid in haemostasis by promoting platelet aggregation and by causing local vasoconstriction.^2,3 It also has p a role in some forms of vascular disease and may contribute to vasospasm of cerebral or coronary arteries, especially with endothelial disfunction or damage⁵ Some evidence has implicated serotonin in the pathogenesis of migraine, peripheral vascular disease, coronary and cerebral vasospasm or essential p p p hypertension. On the other hand, clinical studies have provided evidence that serotonin in the brain is implicated in the state of depression. ^6,7 Many authors consider that blood platelets share a number of properties with serotonergic neurons because of their specific biochemical mechanisms for uptake and storage of amine. ^8,9 Thus, the study of blood serotonin would provide an useful model for certain aspects of neuronal physiology. The present study investigates blood serotonergic mechanisms in diseases with blood vessels disfunction like Thromboangiitis obliterans (Buerger’s disease), g Raynaud’s phenomenon, hypertension and diabetes mellitus as well as in mental disorders as depression and neurosis.