中文摘要：

目的探讨M3受体激动对低氧诱导H9e2细胞损伤的作用及机制。方法采用三气培养建立H9c2细胞低氧损伤模型。实验组分为对照组（A）、低氧组（B）、CCh＋低氧组（C）、4DAMP＋CCh＋低氧组（D）。采用CCK-8法测定细胞存活率，通过流式细胞术检测H9c2细胞凋亡情况；Western blot法检测凋亡蛋白Caspase-3、抗凋亡蛋白Bcl-2及HIF-let和HO-1的表达。结果M3受体激动剂CCh（10mmol/L）可减少低氧诱导的心肌细胞损伤，并可增加心肌Bcl-2、HIF-1α、HO-1的表达，减少Caspase-3表达。但预先应用4DAMP（10nmol/L）阻断M3受体可逆转胆碱作用。结论激动M3受体对低氧诱导H9c2细胞的损伤有保护作用，其机制可能与HIF-1α、HO-1的表达增加有关。

英文摘要：

Objective To observe the effect of activation of M3 receptor on hypoxia damage in cultured H9c2 cell and to investigate its possible mechanisms. Methods A model of Hypoxia damage was performed as cells cul- tured in a tri-gas incubator.Cells were divided into four groups, including control （A）, hypoxia（ B ）, CCh＋hypoxia （C） and 4DAMP ＋ C Ch＋hypoxia（D） .The viability of ceils was determined by CCK-8 assay.Western blot was used to determine Caspase-3, Bel-2, HIF-1α and HO-1 levels.Results Hypoxia mediated myocyte damage was attenua- ted by M3 receptor agonist choline（lOmmol/L） .Pretreatment of cardiac myocytes with choline also increased Bcl- 2, HIF-1α and HO-1, decreased Caspase-3 expression in hypoxia stimulated H9c2 cell.However, blockade of M3 receptor by 4DAMP（10nmol/L） completely inhibited the effects of choline on hypoxia stimulated H9c2 cell.Conclusions Activation of M3 receptor showed protective effect on hypoxia induced damage in cultured H9e2 cell and this effect might be related tomodulating the expression of some genes including HIF-1α and HO-1.