Department of Life Science, College of Natural Sciences, Ewha Womans University, Seoul, Korea.
Yonsei Med J. 2010 Mar;51(2):187-96. doi: 10.3349/ymj.2010.51.2.187. Epub 2010 Feb 12.
Ca(2+) homeostasis plays an important role in myocardial cell injury induced by hypoxia-reoxygenation, and prevention of intracellular Ca(2+) overload is key to cardioprotection. Even though thiopental is a frequently used anesthetic agent, little is known about its cardioprotective effects, particularly in association with Ca(2+) homeostasis. We investigated whether thiopental protects cardiomyocytes against hypoxia-reoxygenation injury by regulating Ca(2+) homeostasis.
Neonatal rat cardiomyocytes were isolated. Cardiomyocytes were exposed to different concentrations of thiopental and immediately replaced in the hypoxic chamber to maintain hypoxia. After 1 hour of exposure, a culture dish was transferred to the CO(2) incubator and cells were incubated at 37 for 5 hours. At the end of the experiments, the authors assessed cell protection using immunoblot analysis and caspase activity. The mRNA of genes involved in Ca(2+) homeostasis, mitochondrial membrane potential, and cellular Ca(2+) levels were examined.
In thiopental-treated cardiomyocytes, there was a decrease in expression of the proapoptotic protein Bax, caspase-3 activation, and intracellular Ca(2+) content. In addition, both enhancement of anti-apoptotic protein Bcl-2 and activation of Erk concerned with survival were shown. Furthermore, thiopental attenuated alterations of genes involving Ca(2+) regulation and significantly modulated abnormal changes of NCX and SERCA2a genes in hypoxia-reoxygenated neonatal cardiomyocytes. Thiopental suppressed disruption of mitochondrial membrane potential (DeltaPsi(m)) induced by hypoxia-reoxygenation.
Thiopental is likely to modulate expression of genes that regulate Ca(2+) homeostasis, which reduces apoptotic cell death and results in cardioprotection.
钙稳态在缺氧再复氧诱导的心肌细胞损伤中起着重要作用，预防细胞内钙超载是心脏保护的关键。虽然硫喷妥钠是一种常用的麻醉剂，但人们对其心脏保护作用知之甚少，特别是与钙稳态有关的作用。我们研究了硫喷妥钠是否通过调节钙稳态来保护心肌细胞免受缺氧再复氧损伤。
分离新生大鼠心肌细胞。将心肌细胞暴露于不同浓度的硫喷妥钠，并立即更换到缺氧室中以维持缺氧。暴露 1 小时后，将培养皿转移到 CO2 孵育箱中，细胞在 37℃下孵育 5 小时。实验结束时，作者使用免疫印迹分析和半胱氨酸天冬氨酸蛋白酶活性评估细胞保护。检查了涉及钙稳态、线粒体膜电位和细胞内 Ca2+水平的基因的 mRNA。
在硫喷妥钠处理的心肌细胞中，促凋亡蛋白 Bax 的表达减少，半胱氨酸天冬氨酸蛋白酶-3 激活和细胞内 Ca2+含量增加。此外，还显示了抗凋亡蛋白 Bcl-2 的增强和与生存有关的 Erk 的激活。此外，硫喷妥钠减轻了涉及钙调节的基因的改变，并显著调节了缺氧再复氧新生儿心肌细胞中 NCX 和 SERCA2a 基因的异常变化。硫喷妥钠抑制了缺氧再复氧引起的线粒体膜电位（DeltaPsi(m)）的破坏。
硫喷妥钠可能调节调节钙稳态的基因表达，减少凋亡性细胞死亡，从而导致心脏保护。
