Arteriolar Responsiveness in Adrenal Crisis in the Dog

Abstract

Blood flow through the peripheral vascular bed served by a femoral artery was measured as adrenalectomized dogs failed in adrenal crisis. Comparisons were made to flows observed in non-adrenalectomized dogs brought to the same arterial presure levels by bleeding. Electrical, pharmacological and mechanical stimuli were used to raise the pressure acutely and the changes in leg conductance in the different groups of animals were compared statistically. No clear deficiencies were found in the ability of adrenalectomized dogs to maintain conductance levels or decrease conductance acutely. This indicated that the leg arterioles were functioning as well in the adrenalectomized dogs as in the controls. The rise in arterial pressure in response to the pressor stimuli always tended to be less in the adrenalectomized animals. Some differences in heart rate change were noted, but they were of hardly sufficient magnitude to explain the diminished pressor response.