Effects of mastoparan on catecholamine release from chromaffin cells.
Release of catecholamines from bovine adrenal chromaffin cells exposed to mastoparan, a wasp venom peptide which activates GTP-binding proteins and phospholipase A2, was evaluated. Release of catecholamines was dependent on mastoparan concentration and time of exposure. This release was, however, independent of extracellular calcium and accompanied by release of the cytoplasmic marker lactate dehydrogenase. Mastoparan also inhibited catecholamine secretion evoked by nicotine, but the peptide had little or no effect on release induced by other secretagogues. These findings suggest that in chromaffin cells mastoparan is not a secretagogue but rather causes cell lysis and blocks nicotinic receptor function.
Wilson
S P
SP
Department of Pharmacology, University of South Carolina School of Medicine, Columbia 29208.
D000313:Adrenal Medulla / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001514:Bee Venoms / Q000494:pharmacology*; D002395:Catecholamines / Q000378:metabolism*; D002417:Cattle; D002478:Cells, Cultured; D002838:Chromaffin System / Q000187:drug effects / Q000378:metabolism*; D004789:Enzyme Activation; D036341:Intercellular Signaling Peptides and Proteins; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009538:Nicotine / Q000494:pharmacology; D010455:Peptides; D010741:Phospholipases A / Q000378:metabolism; D054467:Phospholipases A2; D014862:Wasp Venoms / Q000494:pharmacology*
D001514:Bee Venoms; D002395:Catecholamines; D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; D014862:Wasp Venoms; D009538:Nicotine; C037500:mastoparan; D007770:L-Lactate Dehydrogenase; D010741:Phospholipases A; D054467:Phospholipases A2