INS and diabetes mellitus: 1995; Yibchok‐Anun et al. 2000; Abu‐Basha et al. 2002). For example, the elevated AVP levels observed in uncontrolled diabetes (Vokes et al. 1987) might not only maintain fluid balance, but also stimulate insulin secretion by promoting GLP‐1 release, thereby counteracting the hyperglycaemic state.