Somatostatin and Its Receptors

Somatostatin and its Receptors Chairman: S. Reichlin 1995 The cyclic tetradecapeptide hormone, somatostatin, was first characterized as the major physiological inhibitor of growth hormone release from the pituitary, but has subsequently been shown to inhibit the release of many other physiologically important compounds, including insulin, glucagon, gastrin and secretin. It is therefore a major factor in the control of metabolism. It also functions in the central nervous system as a neurotransmitter/neuromodulator in the control of motor activity and cognitive functions; it may be involved in epilepsy and in Alzheimer's disease. Somatostatin analogues have antiproliferative effects and are now used in the treatment of several forms of cancer. Somatostatin binds to glycoprotein receptors of the seven transmembrane domain superfamily on target cells. These interactions with G proteins, leading to several effects within the cell, including inhibition of adenylyl cyclase and Ca2+ channel activity, stimulation of K+ and tyrosine phosphatase activity, and regulation of intracellular pH. A recent breakthrough in the understanding of the biological roles of somatostatin has been the cloning of five different genes for somatostatin receptors and the consequent elucidation of the primary structures of these receptors. This book contains contributions from a diverse group of scientists and clinicians working on somatostatin and its receptors. Specific topics include somatostatin gene structure, localization and regulation; processing of the inactive prohormone; the distribution of somatostatin receptors and their characterization and regulation; mechanisms of signal transduction; and the design of somatostatin analagues and their possible clinical implications. Related Ciba Foundation Symposia: No. 172: Corticotropin-releasing factor Chairman: Wiley Vale 1993 ISBN 0 471 93448 8 No. 176 The GTPase superfamily Chairman: Frank McCormick 1993 ISBN 0 471 93914 5 No. 191 Non-reproductive actions of sex steroids Chairman: Etienne-Emile Baulieu 1995 ISBN 0 471 95513 2