LAZAROID U-74500A FOR WARM ISCHEMIA AND REPERFUSION INJURY OF THE CANINE SMALL-INTESTINE

BACKGROUND: Although lazaroids have been shown to protect various orga ns from ischemia/reperfusion injury, results obtained in the small int estine have been conflicting. STUDY DESIGN: The canine small intestine was made totally ischemic for 2 hours by occluding the superior mesen teric artery and the superior mesenteric vein with interruption of the mesenteric collateral vessels. A lazaroid compound, U74500A, or a cit rate vehicle was given intravenously to each of the six animals for 30 minutes before intestinal ischemia. Intestinal tissue blood flow lipi d peroxidation, neutrophil infiltration, adenine nucleotides and their catabolites, and histologic changes after reperfusion were determined . RESULTS: Lazaroid treatment attenuated decline of the mucosal and se rosal blood flow after reperfusion. Accumulation of lipid peroxidation products and neutrophils in mucosal tissues was markedly inhibited by the treatment. Postischemic energy resynthesis was also augmented by lazaroid. Morphologically, mucosal architectures were better preserved with lazaroid treatment after reperfusion, and recovered to normal by postoperative day 3 in the treated group and by postoperative day 7 i n control animals. CONCLUSIONS: Lazaroids protect the canine small int estine from ischemia/reperfusion injury by inhibiting lipid peroxidati on and neutrophil infiltration. Dogs are tolerant of 2-hour normotherm ic complete intestinal ischemia.