The protective effect of MPLA preconditioning on hepatic ischemia-reperfusion injury in rats and its mechanism / 中国医师杂志

ABSTRACT

Objective To study the mechanism of monophosphoryl lipid A (MPLA) protecting liver ischemia-reperfusion injury in rats, and explore the hemeoxygenase-1-carbon monoxide-cyclic guanosine monophosphate (HO-1-CO-cGMP) pathway whether involved in MPLA enhance calcitonin gene-related peptides (CGRP) releasing or not. Methods Male SD rats were randomly divided into control group, sham-operated group, hepatic ischemia-reperfusion group, MPLA low, medium and high dose groups (hepatic ischemia-reperfusion + MPLA0. 2,0. 5,1.0 mg/ kg). Hepatic isehemia-reperfusion model was constructed, followed by observation of cell ultrastructure through electron microscope. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and liver tissue levels of CO were determined. HO-1 expression in liver tissue was detected by immunohistochemic, CGRP, eGMP concentration in liver tissue was detected by RIA assay. Results Compared with hepatic isehemia-reperfusion group, the cell damage in MPLA group were relatively minor, and ALT, AST, LDH were significantly decreased (P <0.05), while HO-1, CO, cGMP, CGRP levels were signifi-cantly increased (P < 0.05). HO-1 and CO, CO and cGMP, cGMP and CGRP were obviously positive correlated (P <0.05). Conclu-sion MPLA enhanced CGRP synthesis and release through HO-1-CO-cGMP pathway in liver ischemia / reperfusion, which may be one of the mechanisms of MPLA reducing hepatic ischemia-reperfusion injury in rat.