Variations in ATP-sensitive K+ channel activity provide evidence for inherent metabolic oscillations in pancreatic beta-cells.
The cell-attached configuration of the patch clamp technique was used for studying slow variations in the activity of the ATP-sensitive K+ channels in pancreatic beta-cells isolated from mouse and man. In 0 or 3 mM glucose, the fraction of time the channels were open exhibited oscillations with frequencies in the 0.25-0.40/min range. This phenomenon is a strong argument for inherent fluctuations in the ATP production of the beta-cells. Variations in metabolism may thus be a major determinant for the characteristic large amplitude oscillations of cytoplasmic Ca2+ with equivalent frequency.
Dryselius
S
S
Department of Medical Cell Biology, Uppsala University, Sweden.
Lund
P E
PE
Gylfe
E
E
Hellman
B
B
D000200:Action Potentials; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007515:Islets of Langerhans / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D015221:Potassium Channels / Q000378:metabolism*
D015221:Potassium Channels; D000255:Adenosine Triphosphate; D005947:Glucose