AUTONOMIC INNERVATION OF THREE RAT MUSCULAR ARTERIES

The innervation pattern of three peripheral muscular arteries superficial epigastric, saphenous and tail artery was analyzed in the rat.Some rats were sympathectomized by use of neurotoxin 6-hydroxy-dopamine (6-OHDA) while other normal animals were used as controls. Pieces from the arteries were incubated in a quinacrine (5×10-7 M) containing solution in order to visualize nerve fibers with a selective affinity for the drug (likely peptidergic in nature) or processed for the histochemical detection of peripheral stores of catecholamines or of the acetylcholinesterase activity.No nerve fibers with selective affinity for quinacrine were found, while arteries studied appeared to be supplied with adrenergic and acetylcholinesterase-containing nerve fibers.The 6-OHDA treatment caused the almost complete disappearance of adrenergic and acetylcholinesterase-containing nerve fibers within the three arteries.The findings suggest that rat superficial epigastric, saphenous and tail arteries are supplied only with a sympathetic innervation. The possible physiological significance of the presence of an acetylcholinesterase activity in sympathetic nerves is discussed.