Effects of endotoxin on renal function and hemodynamics

Abstract

The injection of lethal doses of Salmonella typhosa endotoxin in the dog produced an initial (18 sec) transient vasoconstriction followed by a secondary intense vasoconstriction within 5–10 min. Renal arterial pressure remained elevated for 30 min. Since local infusion of phentolamine blocked the secondary renal vasoconstriction it is suggested that the persistent vasoconstriction was due to catecholamine release during the systemic hypotension. After endotoxin injection there was a marked decrease in all renal functions. The hemodynamic effect was eliminated in one kidney by infusing phentolamine locally and holding renal blood flow constant in one group of animals thus enabling comparison of this kidney with the contralateral undisturbed kidney. In the kidney in which vascular effects were eliminated there was no alteration in renal functions after systemic or local endotoxin injection. These data, therefore, show that the principal effect of endotoxin on the kidney is hemodynamic and not nephrotoxic.