Plasma endothelin response to acute hypoglycaemia in adults with Type 1 diabetes.

AIMS: To determine whether acute insulin-induced hypoglycaemia provokes a detectable alteration in peripheral plasma endothelin (ET) concentrations in humans with Type 1 diabetes. METHODS: Serial plasma concentrations of ET were measured in 20 patients with Type 1 diabetes during controlled hypoglycaemia induced by intravenous infusion of soluble insulin. RESULTS: A significant increase was observed in plasma ET concentrations, from 3.80 +/- 0.31 pg/ml at baseline to 6.72 +/- 1.47 pg/ml at 60 min after the onset of the hypoglycaemic reaction (P < 0.05). CONCLUSIONS: Acute insulin-induced hypoglycaemia induces a rise in plasma endothelin concentrations in people with Type 1 diabetes. This finding is consistent with a putative role for ET in the mediation of hypoglycaemia-induced vasoconstriction, and the possible precipitation of macrovascular or microvascular events.