Sensitivity of the Nasal Vessels of the Cat to Chemical Agents After Sympathetic and Parasympathetic Denervation

Abstract

The nasal mucosa was denervated sympathetically and parasympathetically in 19 cats and the effects of phenylephrine, noradrenaline and adrenaline on the vessels were recorded as pressure changes in water-filled balloons located in the nasal cavities. One of the cavities was used as a control in the same cat. The responses to noradrenaline were significantly greater on the sides where the superior cervical ganglia had been extirpated 2 to 8 weeks earlier. These differences are not mainly due to supersensitivity, but probably to effects of dilated blood vessels in the denervated sides. When both sides were sympathetically denervated, one chronically and the other acutely, the responses differed significantly only when the durations were compared and these differences seem to be due to supersensitivity. No significant differences in threshold doses and in responses to supraliminal doses of the drugs could be demonstrated when the postganglionic parasympathetic nerves had been cut.