参三七皂苷Rb_1对缺氧复氧损伤心肌细胞[Ca^(2+)]i含量和钙稳态的影响

Effects of Panax notoginsenoside Rb_1 pretreatment on free calcium and calcium homeostasis in hypoxia/reoxygenation injury model in neonatal rat hypertrophied cardiomyocytes

目的:探讨参三七皂苷Rb1预处理对肥厚心肌细胞缺氧/复氧(H/R)损伤游离钙([Ca2+]i)的影响及其与心肌细胞保护作用与关系。方法:采用体外培养乳鼠心肌细胞,血管紧张素I(IAngII)刺激形成肥厚模型,实验分为7组:①正常对照组(C);②肥厚细胞模型对照组;③肥厚细胞H/R损伤组(H+H/R);④-⑦:Rb1预处理(0.01～10μmol/L)+H/R组;用激光共聚焦显微镜测定[Ca2+]i以及对电压依赖和受体操纵性激动剂KCl,NE诱发细胞内钙离子变化的影响。结果:经缺氧2h复氧1h后,肥厚细胞H/R组[Ca2+]i荧光强度较对照组显著增高,Rb1预处理组细胞内[Ca2+]i荧光强度较肥厚细胞H/R损伤组显著降低(P<0.01)。Rb1预处理使KCl、NE诱发的细胞内钙荧光强度仅增加61.3%和78.9%,升幅显著下降(P<0.01)。结论:参三七皂苷Rb1预处理具有显著减轻H/R肥厚心肌细胞钙超载作用,是其细胞保护作用的重要机制。

Objective： To explore the role of pretreatment of panax notoginsenoside Rb1 on free calcium （[Ca^2＋]i） in protecting effective against hypoxia/reoxygenation（H/R）injury against in neonatal rat hypertrophied cardiomyocytes. Methods： The primary culture of neonatal rat cardiomyocytes was stimulated by angiotensin Ⅱ（AngⅡ） and H/R model was undergone with 2h of hypoxia followed by lh reoxygenation. The eardiomyocytes were divided into 7 groups.①normal control group;②AngⅡ hypertrophy model control group;③ypertrophied cardiomyocytes ＋H/R group; ①-⑦： Rb1 pretreatment （0.01-10 μmol/L） ＋H/R group under voltage-dependent or receptor agonists scanning confocal microscopy in which the [Ca^2＋]i fluorescence intensity were determined and effecting on KCl, NE induced change of [Ca^2＋]i concentration were observed. Results： After hypoxia 2h reoxygenafion followed by l h, the [Ca^2＋]i fluorescence intensity of control group immediately began to increase, the [Ca^2＋]i fluorescence intensity of H/R group was significantly higher（P〈0.01 ）. Pretreatment with Rb1 for 48h, the [Ca^2＋]i fluorescence intensity was significantly lower than that of H/R group. Rb 10.01-10μmol/L pretrement could decrease KCl, NE--indueed increasing of [Ca^2＋]i fluorescence intensity significantly, which increased by only 61.3 and 78.9%（P〈0.01）. Conclusion： These suggested that mechanistic of protective effect of Panax notoginsengsaponins Rb1 against H/R injury may be associated with their reducing intraeellular calcium overload and maintenance of calcium homeostasis of hypertrophied cardiomyocytes.