Inhibition of the Vasomotor System of the Anesthetized Dog by Epinephrine and Norepinephrine
The actions of epinephrine and norepinephrine on the vasomotor system of 55 dogs anesthetized with sodium pentobarbital were investigated with the innervated, perfused leg preparation attached to the body by the sciatic nerve alone. Injections of these catecholamines into the body of the dog produced a dilatation of the vessels in the skeletal muscle of the perfused limb which was unaltered by cholinergic blockade with atropine and no longer occurred after adrenergic blockade with phenoxybenzamine. Vasomotor inhibition by norepinephrine was greatly reduced after baroreceptor inactivation, whereas a much greater proportion of epinephrine's activity remained and is attributed to sympathetic ganglion blockade.
- Received July 31, 1961.
- © 1962 American Heart Association, Inc.