硫化氢后处理对大鼠缺氧-复氧心肌细胞的保护作用

Protective effect of hydrogen sulfide postconditioning on adult rat cardiomyocytes undergoing hypoxiareoxygenation

目的探讨硫化氢(H2S)后处理对缺氧-复氧损伤成年大鼠心肌细胞的影响,评价其心肌保护作用及其可能的机制。方法分离成年SD大鼠心肌细胞,随机均分为四组:正常组(N组)、缺氧-复氧组(HR组)、缺氧后处理组(IPTC组)和H2S后处理组(S组),在激光扫描共聚焦显微镜下检测F-肌动蛋白/G-肌动蛋白荧光强度及Western blot技术检测各组心肌细胞p38MAPK磷酸化(p-p38MAPK)水平;再将上述四组又分为加或不加细胞松弛素D(CyD)两个亚组,激光扫描共聚焦显微镜下检测细胞内Ca2+、pH值荧光强度。结果 HR组、IPTC组和S组F/G-肌动蛋白明显高于N组(P<0.05);IPTC组和S组F/G-肌动蛋白明显高于HR组(P<0.05),且S组明显高于IPTC组(P<0.05)。与无CyD处理比较,CyD处理时四组Ca2+荧光强度明显升高(P<0.05);N组与HR组pH荧光强度升高,IPTC组与S组pH荧光强度降低。无CyD处理时N组、IPTC组和S组Ca2+荧光强度明显低于、pH值荧光强度明显高于HR组(P<0.05);CyD处理后HR组、IPTC组和S组Ca2+荧光强度明显高于,IPTC组和S组pH值荧光强度明显低于N组(P<0.05)。心肌细胞内HR组p-p38MAPK水平明显高于N组、IPTC组和S组(P<0.05)。结论硫化氢后处理可以促进F-肌动蛋白的重塑,稳定缺血缺氧成年大鼠心肌细胞内环境;硫化氢后处理可降低缺血缺氧成年大鼠心肌细胞p38MAPK磷酸化水平。

Objective To explore the relationship between the protective effect of hydrogen sulfide （H2 S ） postconditioning against myocardial hypoxia-reoxygenation and the dynamics of actin. Methods Adult rat cardiomyocytes were isolated and the same hatch cells were divided into 4 groups （n =3）：normal group （group N）,hypoxia-reoxygenation group （group HR）,ischemia postconditioning group （group IPTC）and H2 S postconditioning group （group S）.The four groups were divided into two sub-groups with or without cytochalasin D （CyD）.At the end of reoxygenation,F-actin/G-actin,intracellular calcium ion concentration （Ca2＋ ）and pH value were detected with laser scanning confocal microscopy, meanwhile the level of p-p38MAPK was detected with Western blot.Results The fluorescence intensity of F-actin/G-actin of group HR,group IPTC and group S were significantly higher than that of group N （P 〈0.05）.The fluorescence intensity of Ca2＋ of group HR was higher than that of group N,group IPTC and group S （P 〈0.05）;The intensity of Ca2＋ of all group with CyD treatment was higher than those without （P 〈0.05）;The fluorescence intensity of pHi of group N and group HR with CyD treatment was higher than those without;The fluorescence intensity of pHi of group IPTC and group S was lower than those without;The flu-orescence intensity of pHi of group HR was lower than that of group N,group IPTC and group S （P 〈0.05）, respectively;the pHi of group N and group HR sub-group with CyD treatment was higher than those without correspondingly （P 〈0.05）,however,the pHi of IPTC and S sub-groups were lower than their corresponding groups （P 〈0.05）.The level of p-p38MAPK in group HR was significantly higher than those of other groups （P 〈0.05）;there was no difference among groups N,IPTC and S.Conclusion Hydrogen sulfide postcondi-tioning could promote F-actin to remodel and stabilize the cellular environment.Hypoxia-reoxygenation pro-motes the phosphorylation level of p38MAPK,which could be surpressed by H2 S postconditioning.