Interaction between hemorrhagic hypotension and hypoxia in regulation of renal vascular resistance in unanesthetized rabbits
Busija, D.W.
Circulatory Shock 13(4): 353-359
1984
ISSN/ISBN: 0092-6213 PMID: 6478549 Document Number: 238475
Effects of interaction between hemorrhagic hypotension and hypoxia on the renal circulation were examined in awake rabbits. The hypothesis tested was that renal vasoconstriction during hemorrhagic hypotension is affected by arterial PO2 ). Renal blood flow fell progressively in each group during hypotension, but the magnitude of this response was unaffected by the level of PaO2. In contrast, RVR during severe hypotension was 0.42 .+-. 0.11 and 2.08 .+-. 0.57 mm Hg per 100 g for normoxia and hypoxia, respectively (P < 0.05), and the increase in RVR during severe hypotension compared to normotension was greater in the hypoxic than normoxic group (P < 0.05). In unanesthetized rabbits, hypoxia reduces RBF but does not change RVR significantly during normotension, and hypoxia potentiates the increase in RVR during hemorrhagic hypotension.