ENDOTHELIAL BARRIER RESISTANCE IN MULTIPLE ORGANS AFTER SEPTIC AND NONSEPTIC CHALLENGES IN THE RAT

Local variations in endothelial permeability, hypothesized to play a r ole in the development of multiple-organ injury, were measured by I-12 5-labeled human serum albumin flux and leakage index in rats with a va riety of challenges. The albumin flux significantly increased in the p eritoneum, pancreas, stomach, and liver in acute pancreatitis; in the peritoneum and liver in abdominal sepsis; in the spleen, proximal smal l intestine, colon, liver, lungs, heart, and muscle in bacteremia; in the kidneys, liver, lungs, heart, brain, and muscle in endotoxemia; an d in the peritoneum, proximal small intestine, colon, kidneys, liver, and heart after bradykinin administration. A redistribution of the tis sue blood content, measured by Cr-51-labeled red blood cells, was note d. An increased albumin leakage index, assaying endothelial permeabili ty considering local hemodynamic alterations, was noted in various org ans in the different experimental groups. Thus septic and nonseptic ch allenges induce endothelial barrier injury. The endothelial resistance appears to be organ and/or tissue dependent and associated with a red istribution of blood.