Effects of acute acidosis on renal hemodynamics

Abstract

Perfusing pressure and flow (electromagnetic flowmeter) were measured in the left renal artery of anesthetized dogs, and renal vascular resistance was calculated during normal acid-base status and during progressively severe respiratory acidosis (38 experiments) and metabolic acidosis (8 experiments). Responses to respiratory acidosis were compared for the innervated and denervated kidney. They were also compared with and without local alpha blockade by phenoxy-benzamine. It was shown that moderate acidosis results in renal vaso-dtlatation, whereas more severe acidosis causes vasoconstriction. These responses are largely independent of the renal innervation. The vasodilatation appears to be, most likely, a local effect, whereas vasoconstriction appears to be humoral. The circulatory response is both pH and Pco2 dependent.