[Protection against acute hypoxic/reoxygenation injury to kidney for rabbit with morphine hypoxic preconditioning by observing the expression of caspase-3 protein]

The maintenance of the balance between oxygen supply and oxygen consumption is a key measure in preventing acute kidney hypoxic/reoxygenation injury. Morphine can inhibit metabolism and reduce the oxygen consumption. We tried to investigate the protective effects of morphine hypoxic preconditioning on acute kidney hypoxic/reoxygenation injury in rabbit and its influence on expression of caspase-3 protein. Kidney hypoxic and reoxygenation were induced by making the tested rabbits inhale 8% oxygen for three hours firstly, and then putting them in the air to breathe in normal oxygen for another three hours. Morphine hypoxic preconditioning was induced by administering morphine 3 mg/kg, and then hypoxic of 8% oxygen was induced. Caspase-3 protein expression in renal tissue was assessed by immunohistochemical method. In the present study, the expressions of caspase-3 protein were significantly higher in saline-control hypoxic group than in morphine hypoxic preconditioning group ((29.3+/-5.7)% vs. (12.16+1.23)%, P0.05). These observations suggested that morphine hypoxic preconditioning can protect rabbit against acute kidney hypoxic/reoxygenation injury by decreasing expression of caspase-3 protein.