[Physiologic and therapeutic importance of serotonin and the serotonergic system]

Serotonin (5-hydroxytryptamine, 5-HT) induces various effects in the central nervous system, cardiovascular system and gastrointestinal tract. The response depends primarily on the nature of the 5-HT receptors involved. In the light of the current knowledge about the anatomy and physiology of the serotonergic system and the distribution of the various 5-HT receptors in the organs and tissues, the established and potential therapeutic applications of 5-HT receptor ligands in the treatment of several disorders are discussed. In particular, new selective 5-HT receptor ligands influencing intestinal motility and pain perception such as the partial 5-HT4 receptor agonist tegaserod appear promising for a more specific treatment of irritable bowel disease.