环维黄杨星D对心肌细胞缺氧/复氧损伤的保护作用和对心肌细胞内游离钙浓度的影响

目的:研究环维黄杨星D(CVB-D)对培养乳鼠心肌细胞缺氧/复氧损伤的保护作用和对急性分离大鼠心肌细胞内游离Ca²⁺浓度的影响。方法:采用培养的乳鼠心肌细胞建立缺氧/复氧损伤模型,测定心肌细胞搏动频率、细胞存活率、肌酸激酶(CK)的含量;应用特异性荧光指示剂Fluo-3/AM负载急性分离的大鼠心肌细胞,用激光共聚焦显微镜检测胞内游离钙的变化。结果:缺氧/复氧损伤+环维黄杨星D组(H/R+CVB-D)乳鼠心肌细胞搏动频率、细胞存活率与缺氧/复氧损伤组比较明显升高,CK含量与缺氧/复氧损伤组比较明显下降。对急性分离大鼠心肌细胞内Ca²⁺]i逐步升高,并呈剂量依赖性;在有外钙和无外钙时,CVB-D对胞内钙的升高有显著差异(P<0.05);在无外钙并加入内罗啶孵育后,CVB-D引起的胞内Ca²⁺]i轻度升高,但与无钙组相比无显著性差异(P>0.05)。结论:环维黄杨星D对培养乳鼠心肌细胞缺氧/复氧损伤有保护作用,对急性分离大鼠有升高心肌细胞内游离钙离子浓度的作用,Ca²⁺]的升高既源于内钙释放又源于外钙内流。

Protective Effects of Cyclovirobuxine D exposed to Hypoxia-reoxygenation Injury and Experimental Research of Cyclovirbuxine D on Intracellular Free Ca2+ Concentration on rat Cardiomyocytes

Objective:To study the protective effects of Cyclovirobuxine D exposed to hypoxia-reoxygenation injury on the cultured myocardial cells and effect of intracellular free Ca²⁺ concentration on rat acute isolated cardiomyocytes.Methods: The hypoxia/reoxygenation(H/R) injury model of cultured neonatal rat cardiomyocytes was develop.Myocardial cells beating rate,cell viability,CK were measured.Rat acute isolated cardiomyocytes was measure intracellular free Ca²⁺concentration by calcium fluorescent probe Fluo-3/AM and laser confocal microscope.Results: Compared with H/R group,beating rate,cell viability of H/R+CVB-D was significantly increased.Compared with H/R group,CK of H/R+CVB-D was significantly reduced.In Tyrode CVB-D can elevate Ca²⁺]]_i,its peak values which indicate that the level of Ca²⁺]]_i act in an dose-dependent.Ca²⁺]iwas also signficantly higher in Tyrode than that in no calcium Tyrode(P<0.05).In no calcium Tyrode with ryanodine,CVB-D had no effect on level of Ca²⁺]]_i compared with group of no calcium Tyrode(P>0.05).Conclusion: CVB-D could protect cultured cardiomyocytes against H/R injury.CVB-D was found to increase rat acute isolated intracellular free Ca²⁺ concentration.The increasing of Ca²⁺]]_i was caused by releasing from intracellular stores and extracellular Ca²⁺ influx.