Alterations in Cardiovascular and Renal Hemodynamic Function Following Hypophysectomy in the Dog

Abstract

In studies of unanesthetized dogs, hypophysectomy resulted in a decrease in cardiac output, oxygen consumption, and stroke volume. No appreciable change in arteriovenous oxygen difference, mean femoral arterial pressure, or heart rate was observed. Glomerular filtration rate, renal plasma flow and renal fraction of cardiac output were markedly reduced in the hypophysectomized animals. Renal vascular resistance increased two- to threefold in contrast to a 24% increase in total peripheral vascular resistance. Although a marked reduction in cardiovascular and renal hemodynamic function resulted following hypophysectomy, there was no correlation between the degree of functional change and either the amount of anterior pituitary tissue remaining or the degree of atrophy of the adrenal cortex.