ENDOTHELIN-1 INHIBITS INSULIN-STIMULATION GLUCOSE-UPTAKE IN ISOLATED RAT ADIPOCYTES

A single class of high affinity endothelin-1 (ET-1) binding sites with an apparent Kd of 350 pM and a binding capacity of 69,000 sites/cell was found in isolated rat adipocytes. Whereas ET-1 had no effect on basal glucose uptake, it inhibited insulin-stimulated glucose uptake in both a dose- and time-dependent manner. Insulin binding, however, was not altered. Thus, the present study demonstrates the presence of ET-1 receptor in isolated rat adipocytes and the inhibition of insulin-stimulated (C) 1994 Academic Press, Inc.