Cerebrovascular Response to CO 2 Inhalation in Unanesthetized Goats

Abstract

Summary

The effects of cerebral blood flow of inhalation of 9% CO₂ in air were examined in unanesthetized goats. This procedure increased mean cerebral blood flow from 118 to 185 ml/min per 100 g and was accompanied by a rise in Pco₂ from 33 to 50 mmHg and a fall in pH from 7.41 to 7.26. Administration of phentolamine, propranolol, or atropine into the internal maxillary artery did not modify the normal cerebrovascular response to CO₂ inhalation. It is concluded that blockade of vascular adrenergic of cholinergic atropine-sensitive receptors in the goat has no effect on the cerebral vasomotor response to hypercapnia.