1. Using whole-cell and cell-attached recording configurations, the effects of insulin on leptin activation of @entity855 -sensitive K+ (KATP) channels were examined in the @entity9608 cell line. 2. Whole-cell recordings demonstrated that the leptin-induced hyperpolarization and increased @entity972 conductance are completely occluded by prior exposure to insulin (1-50 nM). In cell-attached recordings, insulin prevented leptin activation of @entity11243 -sensitive KATP channels. Furthermore, insulin (50 nM) slowly and completely reversed the effects of leptin (10 nM), an action not attributable to direct inhibition of KATP channels per se. 3. Low concentrations of @entity2135 ( @entity2135 ; 10-100 nM) failed to prevent leptin activation of KATP channels, although higher concentrations (1 microM) did inhibit leptin actions. 4. The action of insulin was specific for leptin, as the hyperglycaemic agent @entity6335 activated KATP channels following prior exposure to insulin. 5. @entity2307 (1-10 nM) and @entity2306 (10 microM) prevented leptin activation of KATP channels, indicating an involvement of phosphoinositide 3-kinase (PI 3-kinase). 6. In conclusion, leptin activation of KATP channels is counter-regulated by insulin in the @entity9608 cell line. This feedback mechanism may be important in the local integration of hormonal signals which regulate insulin secretion and in alterations of metabolic homeostasis associated with @entity28 and @entity2175 ( @entity2175 ).

Insulin occludes leptin activation of XXXX -sensitive K+ channels in rat CRI-G1 insulin secreting cells.

@entity2175 :: ('MESH:D003924', 'Disease') :: ['non-insulin dependent diabetes mellitus', 'NIDDM'] @entity28 :: ('MESH:D009765', 'Disease') :: ['obesity'] @entity9608 :: ('MESH:D007340', 'Disease') :: ['CRI-G1 insulinoma'] @entity6335 :: ('MESH:D003981', 'Chemical') :: ['diazoxide'] @entity2307 :: ('MESH:C009687', 'Chemical') :: ['Wortmannin'] @entity2306 :: ('MESH:C085911', 'Chemical') :: ['LY 294002'] @entity11243 :: ('MESH:D014044', 'Chemical') :: ['tolbutamide'] @entity2135 :: ('24482(Tax:10116)', 'Gene') :: ['insulin-like growth factor-1', 'IGF-1'] @entity972 :: ('MESH:D011188', 'Chemical') :: ['potassium'] @entity855 :: ('MESH:D000255', 'Chemical') :: ['ATP']
@entity855 :: (MESH:D000255,Chemical) :: ['ATP']
