Decrease in Angiotensin I Conversion by Acute Hypoxia in Dogs

Abstract
Conversion of A[angiotensin I]I to A[angiotensin II]II and inactivation of bradykinin are regulated by converting enzyme. Conversion of AI in vivo is decreased during acute alveolar hypoxia. At a PaO2 [arterial oxygen tension] of 30 mm Hg, conversion of AI is decreased to 1/2 control values. The decrease in AI conversion could not be related to hemodynamic factors in the pulmonary vasculature induced by hypoxia. It may be related to the effects of hypoxia on endothelial cell function or conformation.