The Serotonin Receptors : From Molecular Pharmacology to Human Therapeutics A comprehensive state of the art review of our current understanding of the molecular and structural biology of 5 HT receptors and their potential use for drug discovery. The authors describe the anatomical cellular and subcellular distribution of 5 HT receptors and demonstrate a powerful approach to elucidating their physiological role using knockout mice in which the 5 HT receptors were deleted. They also review our understanding of the physiological role(s) of 5 HT receptors based mainly on studies performed in genetically engineered mice. Highlights include discussions of the behavioral phenotypes of 5 HT receptor knockout animals the molecular biology and pharmacology of 5 HT receptors and insights into the complexity of 5 HT receptor signal transduction.