Characterization of the insulinotropic action of a phospholipase A(2) isolated from Crotalus durissus collilineatus rattlesnake venom on rat pancreatic islets

Author(s)

Nogueira, Tatiane C. A. ^[1] ; Ferreira, Fabiano ; Toyama, Marcos H. ; Stoppiglia, Luiz Fabrizio ; Marangoni, Sergio ; Boschero, Antonio C. ; Carneiro, Everardo M.

Affiliation

^[1] Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia - Brasil

• Document type: Journal article
• Source: Toxicon; v. 45, n. 2, p. 243-248, Feb. 2005.
• Field of knowledge: Biological Sciences - Physiology

Abstract

The ability of PLA2 and crotapotin, isolated from Crotalus durissus collilineatus rattlesnake venom, to stimulate insulin secretion from isolated rat islets was examined. PLA2 and crotapotin stimulated insulin secretion at 2.8 mmol/L glucose, whereas at a high glucose concentrations (16.7 mmol/L) only PLA2 stimulated secretion. Nifedipine (10 ìmol/L) did not alter the ability of PLA2 to increase insulin secretion stimulated by a depolarizing concentration of K+ (30 mmol/L). PLA2 did not affect 14CO2 production but significantly increased the efflux of arachidonic acid from isolated islets. These results indicate that PLA2-stimulated secretion is not dependent on an additional influx of Ca2+ through L-type Ca2+-channels but rather is associated with arachidonic acid formation in pancreatic islets. (AU)