SYMPATHETIC VASODILATOR FIBRES

Abstract

Author''s summary, abridged: "Until 5 yrs. ago evidence for the existence of sympathetic vasodilator fibres had not advanced much beyond the point where it was left by Dale''s demonstration in 1906 that after giving ergotoxine some of the motor effects of sympathetic stimulation were reversed. There was a general belief in the possibility of vasodilator fibres, but evidence obtained from the use of ergotoxine was not accepted by everyone. Recent work has shown that there are important differences in different parts of the body. In the muscles of the dog are cholinergic vasodilators in the sympathetic supply, easily demonstrated without ergotoxine. In the skin of the dog there are no sympathetic vasodilators except in the skin of the ear. In the intestines there are some vasodilators, presumably adrenergic, only to be demonstrated after giving ergotoxine. There are important differences in different spp. In the rabbit and the monkey there are no sympathetic vasodilators to the muscles; in the cat there are a few, while in the dog and the hare there are many.".