Protective effect and mechanism of calf intestinal alkaline phosphatase on liver ischemia/reperfusion injury in rats / 中国组织工程研究

ABSTRACT

BACKGROUND: Ischemia/reperfusion injury in liver is a common pathological process in liver transplantation and lobectomy of liver. Studies have demonstrated that exogenous alkaline phosphatase can reduce toxic effect of endotoxin through dephosphorylation. OBJECTIVE: To establish rat models of ischemia/reperfusion injury in liver and observe the protective effect of calf intestinal alkaline phosphatase (CIAP) preconditioning on ischemia/reperfusion injury. DESIGN, TIME AND SETTING: Randomized controlled animal trial was performed at the laboratory of Department of Digestion, Nanfang Hospital from April to November 2007. MATERIALS Seventy-two SD rats were selected for models of ischemia/reperfusion injury in liver. METHODS: The rats were randomly divided into 3 groups (n=24). In the sham operation group, only the abdominal cavity was open, but not ligated; in normal saline control group, liver blood flow was blocked for 20 minutes, and 1 mL normal saline was injected from tail vein at 5 minutes prior to reperfusion; in CIAP preconditioning group, liver blood flow was blocked for 20 minutes, and 0.5 U/g CIAP was injected from tail vein at 5 minutes prior to reperfusion. MAIN OUTCOME MEASURES: Six animals were sacrificed after ischemia/reperfusion for 1, 3, 6 and 12 hours, respectively to determine the level of serum lipopolysaccharide (LPS) by end-point chromogenic assay; the levels of tumor necrosis factor (TNF-?), interleukin-6 (IL-6) and IL-10 in the serum were detected by ELISA and the filtration of polymorphonuclear neutrophils was measured with myeloperoxidase (MPO) enzyme method. The morphological changes of hepatic tissue were observed using HE staining. RESULTS: The levels of LPS, TNF-?, IL-6, and MPO in the serum were significantly higher in normal saline and CIAP groups than in sham operation group (P