Inhibition of K-Channels in Insulin Secreting Cells
The major physiological stimulus for insulin secretion from pancreatic β-cells is an elevation of the plasma glucose concentration. The initial effect is to evoke membrane depolarization4 followed by a cyclical pattern of electrical activity consisting of slow waves of depolarization with action potential-like spikes.9,12 Tracer flux studies have indicated that glucose metabolism is associated with a decrease in membrane K+ permeability17 and Ashcroft, Harrison and Ashcroft2 have demonstrated glucose-induced closure of single K-channels in isolated rat pancreatic β-cells (this book).
KeywordsPancreatic Islet Cell Membrane Patch Glyceraldehyde Phosphate Excise Membrane Patches3 Plasma Glucose Concentra
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