Characterization of potassium channels in pancreatic β cells from ob/ob mice

FEBS Letters

Kukuljan, Manuel¹  Li, Min Yi¹  Atwater, Illani¹ 

[1] Laboratory of Cell Biology and Genetics, NIDDK, National Institutes of Health, Building 8, Room 403, Bethesda, MD 20892, USA

关键词: Pancreatic β cell;    Potassium channel;    Diabetic mouse;    Sulphonylurea;   

DOI  :  10.1016/0014-5793(90)81518-S

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The patch-clamp technique in the cell-attached mode was used to study the K channels present in the membrane of cultured pancreatic β cells from ob/ob mice. Three types of K⁺ channels were regularly observed, with conductances of 64, 20 and 146 pS. The conduction and kinetic properties of the 64 pS channel were similar to those of the ATP-sensitive potassium channel from normal β cells. Furthermore, glucose blocked the activity of this channel at the same concentrations as that reported for normal cells. The 20 pS and the 146 pS were insensitive to glucose. The latter K⁺ channel appears to be similar to the large conductance voltage-activated potassium channels described in normal rodent β cells. Thus, potassium channels in ob/ob pancreatic β cells in culture are in most respects normal. Other factors may account for the abnormal electrical response to glucose of ob/ob pancreatic islets, such as reversible impairment of their function in vivo or defects not related to potassium permeability.

【 授权许可】

Unknown