The ATP-sensitivity of K+ channels in rat pancreatic B-cells is modulated by ADP.
ATP-sensitive K+ channels in inside-out membrane patches from dispersed rat pancreatic B-cells were studied using patch-clamp methods. The dose-response curve for ATP-induced channel inhibition was shifted to higher concentrations in the presence of ADP (2 mM). In glucose-free solution, the total intracellular concentration of ATP was 3.8 mM and of ADP 1.5 mM; glucose (20 mM) increased ATP and decreased ADP by approx. 40%. These results suggest that both ADP and ATP may be involved in regulating the activity of the glucose-sensitive K+ channel in intact B-cells.
D000244:Adenosine Diphosphate / Q000378:metabolism / Q000502:physiology*; D000255:Adenosine Triphosphate / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D007473:Ion Channels / Q000502:physiology*; D007515:Islets of Langerhans / Q000502:physiology*; D011188:Potassium / Q000378:metabolism; D051381:Rats
D007473:Ion Channels; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D005947:Glucose; D011188:Potassium