Responses of the isolated perfused mesenteric vasculature from diabetic rats: the significance of appropriate control tissues.

The influence of streptozotocin-induced diabetes on the contractile responses of the rat isolated perfused mesenteric vascular bed was determined. Two control groups were used, age-matched, fed ad-libitum rats and age-matched, food-restricted rats which were weight-matched to the diabetic group. Two months after the induction of diabetes there was a nonspecific decrease in contractile responsiveness of the mesenteric vascular bed from the diabetic rats to nerve stimulation, and to intraluminal norepinephrine and KCI compared to the responses of the control groups. There was no difference in the responsiveness of the two control groups to these vasoconstrictor treatments. The diabetes-induced depression of responses could be due to changes in vascular smooth muscle function, with an additional contribution of an abnormality in sympathetic neuronal function.