The nitric oxide donor molsidomine improves survival and reduces hepatocyte apoptosis in cholestasis and endotoxemia

BACKGROUND: Cholestasis and endotoxemia have been demonstrated to cause hepatocyte apoptosis through caspase-mediated pathways. In vitro nitric oxide (NO) donors reduce hepatocyte apoptosis and caspase activation in several models. The nitric oxide donor molsidomine improves survival in an in vivo model of endotoxemia. We tested the effect of molsidomine on survival and hepatocyte apoptosis in a model of obstructive jaundice and endotoxemia. STUDY DESIGN: Sprague-Dawley rats underwent common bile duct ligation on day 1. On day 3, animals were given either 100 mg/kg of molsidomine or an equivalent volume of saline, and 30 minutes later they were given endotoxin 3 mg/kg or 10 mg/kg intravenously. Animals were sacrificed 4 or 16 hours after endotoxin injection. Serum samples were analyzed for alanine aminotransferase and frozen liver samples were analyzed for caspase 3 activity. Paraffin-embedded liver sections were assayed for apoptosis using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay. Survival was measured in a separate experiment in which animals underwent the same protocol, but were given three different doses of endotoxin and were observed for 72 hours before sacrifice. RESULTS: At endotoxin 3 mg/kg, the 72-hour survival in saline-treated animals was 92%, which decreased to 45% at 10 mg/kg and to 29% at 15 mg/kg. All of the molsidomine-treated animals survived all endotoxin doses. Alanine aminotransferase was reduced in molsidomine-treated animals compared with those treated with saline. Apoptosis was attenuated in molsidomine-treated animals. Caspase 3 activity was decreased in molsidomine-treated animals compared with those given saline. CONCLUSIONS: Molsidomine attenuates caspase activation and hepatocyte apoptosis and improves survival after cholestatic endotoxic injury. (C) 2003 by the American College of Surgeons.