Respiration of Chemodenervated Goats in Acute Metabolic Acidosis

摘要

In awake goats before and after ablation of carotid bodies (CBx) we studied the effect of acute metabolic acidosis (AMA) produced by intravenous infusion of HC1 on composition of arterial blood and CSF, and on ventilatory responsiveness to hyperoxic C02 rebreathing. AMA caused decrease in PaC02 (breathing air at rest) indicating that alveolar ventilation was increased relative to C02 production; position of C02 response curves was shifted toward lower values of PC02. These changes were similar before and after CBx, though the levels of PC02 in arterial blood during air breathing at rest, and in expired gas at a given level of ventilation during C02 rebreathing, were higher after CBx. We conclude that a respiratory adaptation to AMA does occur in goats deprived of peripheral chemoreceptors, and is probably mediated by the central chemoreceptors.