Stimulation Of Sympathetic Nerve Fibres To The Nose In Cats

Abstract

The sympathetic innervation to the nose of the cat has been investigated by two methods. Venous flow from one nose cavity has been recorded as drops of blood and simultaneously the nasal patency from the same cavity has been estimated by a balloon technique. More than one sympathetic pathway giving decreased venous flow and increased nasal patency in the nose cavity has been demonstrated. Some of the sympathetic postganglionic nerve fibres travel in the vidian nerve together with parasympath-etic preganglionic nerve fibres. When the vidian nerve was stimulated with low intensities and high frequencies the parasympathetic effects dominated. With high intensities and low frequencies, the sympathetic effects dominated. In one of 17 cats no sympathetic fibres were found in the vidian nerve. Other sympathetic pathways to the nose are discussed. Finally, stimulation of the contralateral cervical sympathetic nerve affects the nose cavity.