Heparin inhibits IP3‐induced Ca2+ release in permeabilized pancreatic β‐cells

Abstract
Heparin was found to inhibit the Ca2+ release induced by inositol 1,4,5-trisphosphate (IP3) in permeabilized pancreatic β-cells obtained from obese hyperglycemic mice. The effect of heparin was dose-dependent and not due to inhibition of Ca2+ uptake into the IP3-sensitive pool. The effect appeared specific for heparin and was not reproduced by other polysaccharides such as chondroitin sulfates. Heparin might consequently be a useful tool when investigating the molecular mechanism whereby IP3 mobilizes Ca2+.