腺苷受体激活对体外培养心肌细胞缺氧再给氧损伤的保护效应

Protective effects of adenosine on hypoxia-reoxygenation-induced injury of in vitro cultured myocardial cells

目的:观察腺苷A1受体激动剂和A2受体激动剂对体外培养乳鼠心肌细胞缺氧/再给氧损伤的影响。方法:实验于2005-09/2006-06在辽宁医学院药理实验室完成。生后2～4d的SD大白鼠乳鼠260只,以培养的大鼠乳鼠心肌细胞为模型,在造成心肌细胞缺氧/再给氧损伤模型后,观察分别给正常含糖含氧的Hanks液组,缺氧+腺苷A1受体激动剂再给氧组,缺氧+腺苷A1受体激动剂+腺苷A1受体拮抗剂再给氧组,缺氧+腺苷A2受体激动剂再给氧组,缺氧+腺苷A2受体激动剂+腺苷A2受体拮抗剂再给氧组对心肌细胞活力及心肌细胞搏动频率的影响,以及对心肌细胞培养液上清中乳酸脱氢酶含量的影响。结果:腺苷A1受体激动剂可以明显增加心肌细胞的活力,显著提高心肌细胞的搏动频率,使心肌细胞的搏动频率在缺氧/再给氧后明显恢复,还可以使心肌细胞培养液上清中乳酸脱氢酶的含量明显降低。并且这种保护作用可以被腺苷A1受体拮抗剂所拮抗。腺苷A2受体激动剂和A2受体拮抗剂对培养的心肌细胞缺氧/再给氧损伤无明显影响。结论:腺苷受体激活对培养的心肌细胞缺氧/再给氧损伤有保护作用,其保护作用可能是通过激动腺苷A1受体途径来实现的。

AIM： To explore the effects of adenosine A1 receptor agonist and adenosine A2 receptor agonist on hypoxia-reoxygenation-induced injury of in vitro cultured cardiac myocytes in neonatal rats. METHODS： The experiment was carried out in the Laboratory of Pharmacology at Liaoning Medical University from September 2005 to June 2006. A total of 260 neonatal albino rats within 2-4 days postborn were used for the cultured myocardial cell model, then the vitality of cells, beating frequency of cells and the release of lactate dehydrogenase in the supematant of culture medium were observed after hypoxia-reoxygenation-induced injury in the presence or absence of adenosine A1 receptor agonist and adenosine A2 receptor agonist or their angonists. RESULTS： A1 receptor agonist significantly enhanced the vitality of cells, restored the cellular beating frequency and reduced the release of lactate dehydrogenase in the supernatant of culture medium after hypoxia-reoxygenation-induced injury. The protective effects were abolished by A1 receptor antagonist. A2 receptor agonist and antagonist had no effects on the hypoxia-reoxygenation-induced injury. CONCLUSION： Adenosine receptor activation protects the cultured myocardial cells against hypoxia-reoxygenation-induced injury by activating the A1 receptor.