Altered hyperemic response of the coronary arterial bed in alloxan-diabetes.

Reactive hyperemic responses of the coronary arterial bed, provoked by asphyxia or clamping of the coronary artery, were compared in alloxan-diabetic and metabolically healthy dogs. In alloxan-diabetic dogs the response of the coronary arterial bed lasted longer, and its reactivity to hypoxia was lower. Treatment with adenosine caused less vasodilation in diabetic animals than in controls. These changes may be due to the altered reactivity of diabetic vascular smooth muscle.