吗啡缺氧预处理对兔缺氧/复氧肾脏损伤的保护作用和caspase-3的影响

Protection Against Acute Hypoxic/Reoxygenation Injury to Kidney for Rabbit with Morphine Hypoxic Preconditioning by Observing the Expression of Caspase-3 Protein

维持机体氧供与氧耗相对平衡是防治缺氧/复氧损伤的重要措施。吗啡可降低代谢,降低氧耗。细胞凋亡是缺血再灌注损伤发病机制中的重要环节,半胱氨酸蛋白酶3(caspase-3)是凋亡的关键酶和执行者。本文拟通过观察缺氧/复氧损伤肾脏组织中caspase-3蛋白的变化,探讨吗啡缺氧预处理发挥肾脏保护作用的可能机制。经自制面罩吸入8%O23 h后吸入空气复氧3 h,建立全身缺氧/复氧肾损伤兔动物模型,缺氧/复氧结束后分别取肾脏组织,采用Envision两步法行caspase-3免疫组化染色。实验结果表明:正常对照组肾脏组织中极少的caspase-3阳性细胞表达。单纯缺氧/复氧组和吗啡缺氧预处理组阳性蛋白表达指数分别为(29.3±5.7)%和(12.16+1.23)%(P<0.05)。结果提示:吗啡缺氧预处理可以下调兔肾脏缺氧/复氧损伤时caspase-3的表达,进而对缺氧/复氧损伤肾脏组织发挥保护作用。

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 3mg/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.