Ghrelin is present in pancreatic α-cells of humans and rats and stimulates insulin secretion. - Date,Y.; Nakazato,M.; Hashiguchi,S.; Dezaki,K.; Mondal,MS.; Hosoda,H.; Kojima,M.; Kangawa,K.; Arima,T.; Matsuo,H.; Yada,T.; Matsukura,S. (Diabetes, 2002)