Streptozotocin diabetes in the pregnant rat induces cardiovascular dysfunction in adult offspring

Severe diabetes in pregnant rats produces persistent metabolic consequences in adult offspring. This study investigated whether diabetes in pregnant r ats could also lead to cardiovascular abnormalities in the adult offspring. Blood pressure, heart rate and in vitro vascular reactivity of small arter ies were evaluated in female adult offspring of control rats and of rats re ndered diabetic with streptozotocin. Rise in blood pressures were similar i n both groups of offspring but heart rate was lower in the diabetic offspri ng (p < 0.05). The rise in blood pressure associated with infusion of a nit ric oxide synthase inhibitor was similar in both groups, but the associated decrease in heart rate was more pronounced in diabetic offspring (p < 0.01 ). Small mesenteric arteries from this group showed enhanced sensitivity to noradrenaline (p < 0.05) and abnormal endothelium-dependent relaxation to acetylcholine (p < 0.01) and bradykinin (p < 0.05). Reduction in acetylchol ine induced relaxation, reflected reduced synthesis of nitric oxide or a cy clooxygenase product and was not attributable to an endothelium-derived hyp erpolarizing factor. Sensitivity to exogenous nitric oxide was normal. A su bgroup of pups born to diabetic dams were suckled by control maternal dams and a subgroup of those born to controls by diabetic dams. Suckling was an important determinant of impaired growth; offspring of diabetic rats suckle d by their own mother and those of control rats by diabetic darns showed im paired growth rates whereas growth of offspring of diabetic rats suckled by control dams paralleled those of control rats suckled by their own mother.