passages.id: IEPA.d115.s277
passages.text: Overexpression of G11alpha and isoforms of phospholipase C in islet  beta-cells reveals a lack of correlation between inositol phosphate  accumulation and insulin secretion.
passages.id: IEPA.d115.s278
passages.text: It has been suggested that insulin secretion from pancreatic islets may be  mediated in part by activation of phospholipases C (PLCs) and  phosphoinositide hydrolysis.
passages.id: IEPA.d115.s279
passages.text: The purpose of this study was to determine  whether the relatively modest fuel-stimulated insulin secretion responses  of rodent beta-cell lines might be explained by inadequate expression or  activation of PLC isoforms.
passages.id: IEPA.d115.s280
passages.text: Adenovirus-mediated overexpression of PLC-delta1, -beta1, or  -beta3 in INS-1 or betaG 40/110 cells results in little or no enhancement  in inositol phosphate (IP) accumulation and no improvement in insulin  secretion when the cells are stimulated with glucose or carbachol, despite  the fact that the overexpressed proteins are fully active in cell  extracts.
passages.id: IEPA.d115.s281
passages.text: Overexpression of PLC-beta1 or -beta3 in normal rat islets  elicits a larger increase in IP accumulation but, again, has no effect on  insulin secretion.
passages.id: IEPA.d115.s282
passages.text: Because the effect of carbachol on insulin secretion is  thought to be mediated through muscarinic receptors that link to the Gq/11  class of heterotrimeric G proteins, we also overexpressed G11alpha in  INS-1 cells, either alone or in concert with overexpression of PLC-beta1  or -beta3.
passages.id: IEPA.d115.s283
passages.text: Overexpression of G11alpha enhances IP accumulation, an effect  slightly potentiated by co-overexpression of PLC-beta1 or -beta3, but  these maneuvers do not affect glucose or carbachol-stimulated insulin  secretion.