OBJECTIVE: To investigate whether tirilazad mesylate, a 21-aminosteroid, protects the small intestinal mucosa from injury following total warm or cold ischemia and reperfusion. DESIGN: Randomized vehicle-controlled experimental study. SETTING: A university department of surgery. ANIMALS: Wistar rats. The warm ischemia series preceded the cold ischemia series. Animals were randomized within each series. Microscopic evaluation was performed on coded tissue slides. INTERVENTIONS: Warm ischemia was induced by a hydrostatic pressure cuff inflated to 10 mm Hg above the systolic arterial pressure for 60 minutes. Cold ischemia was studied after small intestinal transplantation. The transplant was stored for 5 hours in University of Wisconsin solution at 8 degrees C. Ischemia was followed by 60 minutes of reperfusion. In both series, tirilazad mesylate (3 mg/kg) or methylprednisolone sodium succinate (30 mg/kg) was given. Controls were given tirilazad vehicle or saline solution. MAIN OUTCOME MEASURE: Microscopic grade of small intestinal mucosal injury. RESULTS: Mucosal injury was evident in all groups of animals that were subjected to warm or cold ischemia. Reperfusion following cold ischemia induced a significant reperfusion injury. Neither tirilazad nor methylprednisolone protected the small intestinal mucosa during ischemia or reperfusion. CONCLUSION: Mucosal injury following warm or cold intestinal ischemia and reperfusion is caused by factors other than or in addition to lipid peroxidation, which is preventable by use of a 21-aminosteroid.
OBJECTIVE: To investigate whether tirilazad mesylate, a 21-aminosteroid, protects the small intestinal mucosa from injury following total warm or cold ischemia and reperfusion. DESIGN: Randomized vehicle-controlled experimental study. SETTING: A university department of surgery. ANIMALS: Wistar rats. The warm ischemia series preceded the cold ischemia series. Animals were randomized within each series. Microscopic evaluation was performed on coded tissue slides. INTERVENTIONS: Warm ischemia was induced by a hydrostatic pressure cuff inflated to 10 mm Hg above the systolic arterial pressure for 60 minutes. Cold ischemia was studied after small intestinal transplantation. The transplant was stored for 5 hours in University of Wisconsin solution at 8 degrees C. Ischemia was followed by 60 minutes of reperfusion. In both series, tirilazad mesylate (3 mg/kg) or methylprednisolone sodium succinate (30 mg/kg) was given. Controls were given tirilazad vehicle or saline solution. MAIN OUTCOME MEASURE: Microscopic grade of small intestinal mucosal injury. RESULTS:Mucosal injury was evident in all groups of animals that were subjected to warm or cold ischemia. Reperfusion following cold ischemia induced a significant reperfusion injury. Neither tirilazad nor methylprednisolone protected the small intestinal mucosa during ischemia or reperfusion. CONCLUSION:Mucosal injury following warm or cold intestinal ischemia and reperfusion is caused by factors other than or in addition to lipid peroxidation, which is preventable by use of a 21-aminosteroid.