摘要
目的观察微管稳定剂Taxol对缺氧心肌细胞Cx43表达和分布的影响,探讨其作为新的抗心律失常药物的潜在价值。方法酶解法分离的大鼠心肌细胞缺氧120 min,并以不同浓度的Taxol干预;台盼蓝排斥实验测定细胞存活率;免疫印迹检测Cx43的蛋白表达,免疫荧光染色后激光共聚焦显微镜观察分析Cx43的分布。结果 Taxol在0.1～10nmol·L-1浓度下成剂量依赖性地提高杆状细胞数,促进细胞存活,而100 nmol·L-1～10μmol·L-1浓度下杆状细胞数开始减少;缺氧时心肌细胞Cx43蛋白表达下降,Taxol呈剂量依赖性地改善心肌细胞的Cx43表达,但过量的Taxol则抑制心肌Cx43;正常心肌细胞Cx43主要分布在细胞两端,缺氧时细胞侧边出现Cx43分布。0.1～10nmol·L-1的Tax-ol呈剂量依赖性地抑制侧边Cx43,100 nmol·L-1～10μmol·L-1的Taxol也抑制心肌细胞两端Cx43。结论缺氧导致心肌细胞Cx43表达降低,分布紊乱,低剂量微管稳定剂Tax-ol可以明显地保护缺氧心肌Cx43,具有潜在的抗缺血性心律失常的临床应用价值。
Objectives： Aim To observe the effects of microtubule stabilizer （ Taxol） on connexin43 （ Cx43） expression and distribution of cardiac myocytes and investigate its new value as an anti-arrhythmic agent. Methods Cardiac myocytes isolated from adult rats were exposed to hypoxia for 120 min with or without taxol （ a kind of microtubule stabilizer） in different concentrations. Cellular survival was assayed by trypan blue dye-exclusion. Cx43 expression was determined by western blots. Cx43 distribution was detected by immunofluorescence staining and observed under laser scanning confocal microscope. Results The cell viability under hypoxic condition was reduced significantly which showed only few numbers of rod-shaped cells. Taxol promoted cell survival in a dose-dependent man-ner at the range of 0. 1 ～ 10 nmol·L - 1 . At the range of 100 nmol·L - 1 ～ 10 μmol·L - 1 ,taxol lead to reduced cell survival. Taxol in a dose-dependent manner improved Cx43 expression even although excessive taxol also suppressed Cx43. Cx43 was located in both ends of intact cardiac myocytes （ intercalated disk） and redistributed in both sides of the cell under hypoxic conditions. Taxol dose-dependently inhibited lateralization of Cx43 in lower concentration and further decreased Cx43 in the intercalated disk. Conclusions Cx43 redistribution induced by hypoxic is protected by low dosage of taxol. Microtubule stabilizer may be acted as a new anti-arrhythmic agent.
出处
《中国药理学通报》
CAS
CSCD
北大核心
2012年第11期1607-1610,共4页
Chinese Pharmacological Bulletin
基金
国家自然科学基金资助项目(No 81200142)
安徽省自然科学基金资助项目(No 1208085QH156
1208085MH129)
弋矶山医院人才引进科研基金(No YR201001)
关键词
心肌
缺氧
微管
缝隙连接
泰素
连接蛋白连
cardiac myocytes
hypoxia
microtubule
gap junction
Taxol
connexin
