Figure 1. Exogenous ghrelin and endogenous islet-derived ghrelin attenuate glucose-induced insulin release in a GHSR-dependent manner in mouse islets.

(A) Glucose (8.3 mM)-induced insulin release in isolated islets was inhibited by exogenous ghrelin (10 nM) in wild-type mice. In isolated islets from GHSR-null mice, ghrelin (1  nM) failed to attenuate glucose (8.3 mM)-induced insulin release. The glucose (8.3 mM)-induced insulin release per se was larger in GHSR-null mice than wild-type mice (n = 8–12 tubes of batch incubation). *P < 0.05. (B) Insulin content per islet (n = 8 tubes) and (C) mean islet size (n = 79–107 islets) were identical between wild-type and GHSR-null mice.