| First Author | Eto K | Year | 2002 |
| Journal | Diabetes | Volume | 51 |
| Issue | 1 | Pages | 87-97 |
| PubMed ID | 11756327 | Mgi Jnum | J:107165 |
| Mgi Id | MGI:3620366 | Doi | 10.2337/diabetes.51.1.87 |
| Citation | Eto K, et al. (2002) Phosphatidylinositol 3-kinase suppresses glucose-stimulated insulin secretion by affecting post-cytosolic [Ca(2+)] elevation signals. Diabetes 51(1):87-97 |
| abstractText | The role of phosphatidylinositol (PI) 3-kinase in the regulation of pancreatic beta-cell function was investigated. PI 3-kinase activity in p85 alpha regulatory subunit-deficient (p85 alpha(-/-)) islets was decreased to approximately 20% of that in wild-type controls. Insulin content and mass of rough endoplasmic reticula were decreased in beta-cells from p85 alpha(-/-) mice with increased insulin sensitivity. However, p85 alpha(-/-) beta-cells exhibited a marked increase in the insulin secretory response to higher concentrations of glucose. When PI 3-kinase in wild-type islets was suppressed by wortmannin or LY294002, the secretion was also substantially potentiated. Wortmannin's potentiating effect was not due to augmentation in glucose metabolism or cytosolic [Ca(2+)] elevation. Results of p85 alpha(-/-) islets and wortmannin-treated wild-type islets stimulated with diazoxide and KCl showed that inhibition of PI 3-kinase activity exerted its effect on secretion, at least in part, distal to a cytosolic [Ca(2+)] elevation. These results suggest that PI 3-kinase activity normally plays a crucial role in the suppression of glucose-stimulated insulin secretion. |
