Effect of Simultaneous Use of Opium and Ischemic Preconditioning on Ischemia/Reperfusion Injury in the Rat Liver

Background: Ischemia preconditioning (IPC) is known as a protective procedure against the injury induced by ischemia/reperfusion (IR) injury. There is also evidence that the administration of opioids may have the same effects on the injury. Objectives: The aim of this study was to investigate the ameliorative effects of simultaneous use of opium and IPC on lobar IR injury in the rat liver. Methods: Twenty-five adult male rats were randomly divided into five groups: 1) Sham-operated, 2) IR, 3) IR+IPC, 4) Opium+IPC+IR and 5) Naloxone+opium+IPC+IR. At the end of the reperfusion, blood and tissue samples were obtained to assay alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the blood, as well as to determine oxidative stress by measuring malondialdehyde (MDA) levels, total antioxidant capacity (TAC) values, and superoxide dismutase (SOD) and catalase (CAT) activities in the liver tissues. Results: The levels of ALT, AST and MDA were significantly increased in the IR group compared to the sham-operated group (P<0.05). However, the application of IPC and IPC+opium significantly decreased the release of these enzymes, while the simultaneous application of opium and IPC had a stronger restorative effect on the IR injury (P<0.05). The recovery effects induced by opium+IPC in terms of TAC, SOD and CAT were also higher than that of the IPC alone. However, the use of naloxone significantly inhibited the protective effects induced by the opium. Conclusion: The simultaneous use of opium and IPC is able to accelerate the protective effects of IPC on IR injury.