Ulinastatin Reduces T Cell Apoptosis in Rats with Severe Acute Pancreatitis

Purpose: To investigate the immunoregulative effects of ulinastatin (UTI) on T lymphocytes apoptosis in rats with severe acute pancreatitis (SAP) and to elucidate its underlying molecular mechanism. Methods: Thirty six Wistar rats were randomly divided into 3 groups (n =12): sham, SAP model and UTI-treated group. SAP model was established by intrapancreatobiliary duct injection of 5% sodium taurocholate. A bolus of 10000 U/kg UTI was intravenously injected after SAP establishment. T cell apoptosis was determined by Annexin-V/PI double-staining. Oxidative stress was evaluated by examining changes in the levels of reactive oxygen species (ROS). Total superoxide dismutase (SOD) in serum was tested by hydroxylamine colorimetric assay, and malondialdehyde levels were examined by thiobarbituric acid assay. Mitochondrial function was evaluated by analyzing mitochondrial membrane potential (MMP) and mitochondrial permeability transition pore (MPTP). Results: We found CD4+ T cells (32.10±2.87% vs. 45.22±4.38%, P