Effects of glucose injection and cold exposure on secretory responses of insulin, glucagon and 11-hydroxycorticosteroids in piglets.

The effect of an intravenous injection of glucose (1.25 mmoles/kg) on plasma insulin, glucagon and 11-hydroxycorticosteroids (11-OHCS) was compared in castrated Landrace piglets between the thrmoneutral (T.N., 22°C) and the cold (2°C) environment. Glucose-induced insulin secretion was accelerated by the cold exposure, differently from the previous results obtained from sheep. Plasma glucagon did not change after the glucose injection in T.N. environment, but declined temporarily 3 min after the glucose injection in the cold environment. Plasma 11-OHCS after the glucose injectjion declined slightly in T.N. environment, and more evidently in the cold environment. The magnitude of the reduction in plasma 11-OHCS was the largest on day 4 of the cold exposure.