Consequences of the saphenous artery denervation under normal and chronically lowered blood pressure in rats

We studied constrictor responses of saphenous artery after sympathetic denervation in normotensive rats and rats with chronic regional hypotension. Abdominal aorta was partially occluded in Wistar rats distally to the renal arteries, lowering blood pressure in the hindquarters by about 40%, a week later to denervate saphenous artery the femoral nerve was cut. The density of periarterial nerve plexus and neurogenic responses of the vessel restored partially in 2 weeks and completely in 6 weeks after the surgery; the chronic hypotension did not modify the dynamics of reinnervation. Arteries of both groups of rats demonstrated higher sensitivity to noradrenaline during 6 weeks after denervation, whereas vessel sensitivity to serotonin was enhanced only in normotensive rats. Therefore, chronic hypotension may prevent postdenervation hypersensitivity of vascular smooth muscle to vasoconstrictors.