硫化氢对自发性高血压大鼠心肌重构的作用及机制研究

Effect of H2S on myocardial remodeling in rat model of SHR

目的探讨硫化氢H2S对自发性高血压大鼠(SHR)间隙连接蛋白40(Cx40)、43(Cx43)表达的调控作用,以及与心肌重构的关系。方法取8周龄雄性SHR16只,随机分为SHR对照组(n=8)、SHR+硫氢化钠NaHS组(n=8);取同周龄的正常Wistar京都(WKY)雄性大鼠8只,设为WKY组。SHR+NaHS组腹腔注射NaHS56μmol/(kg·d),SHR对照组和WKY组每日腹腔注射等量生理盐水,持续8周。用分光光度计检测各组大鼠外周血和心肌组织中H2S含量;通过HE染色及Masson三色染色观察H2S对心肌的病理学改变;通过免疫组织化学检测3组大鼠心脏组织中Cx40、Cx43表达位置的变化;运用Westernblotting检测3组大鼠心脏组织中Cx40、Cx43及α-平滑肌肌动蛋白(α-SMA)、骨桥蛋白(OPN)表达量的变化。结果与WKY组大鼠比较,SHR组大鼠外周血及心肌组织中H2S含量减少(P<0.05),NaHS干预后SHR外周血及心肌组织中H2S含量增加(P<0.05);与WKY组大鼠比较,SHR组大鼠心肌纤维结构排列较为紊乱,NaHS干预后SHR心肌纤维排列较为整齐;SHR组大鼠心肌中的Cx40、Cx43表达增加且分布紊乱,SHR+NaHS组大鼠心肌中的Cx40、Cx43分布较规整;且SHR组大鼠心肌中Cx40、Cx43、α-SMA、OPN表达升高(P<0.05),SHR+NaHS组大鼠心肌中Cx40、Cx43、α-SMA、OPN表达降低(P<0.05)。结论H2S可能通过调控Cx40、Cx43的表达来改善SHR心肌重构。

Objective To explore the effect of hydrogen sulfide(H2S)on myocardial remodeling in rat model of spontaneously hypertensive rats(SHR).Methods Sixteen 8-week-old male rate were randomly divided into three groups(n=8):normal control group,SHR group,and SHR+NaHS group.Rats in SHR+NaHS group were intraperitoneally injected with sodium sulfide on daily basis(56μmol/kg)for 8 weeks,while normal saline were administrated in SHR group and WKY group.The content of H2S in peripheral blood and myocardium of rats in each group was determined by spectrophotometry.Pathological changes of myocardium were observed by hematoxylin eosin(HE)staining and Masson trichrome staining.Immunohistochemistry was used to detect the expression of gap junction protein 40,43(Cx40,Cx43)in the three groups.Western blotting was used to detect the expression of Cx40,Cx43,smooth muscle actin(α-SMA)and osteopontin(OPN).Results Compared with WKY rats,the content of H2S in peripheral blood and myocardium of SHR group decreased(P<0.05),which was restored with treatment of NaHS(P<0.05).Compared with the WKY group,rats in SHR group experienced disordered myocardial fiber structure,which were normalized with NaHS intervention.IHC results showed that the expression of Cx40,Cx43 in myocardium of SHR group was increased though distributed disorderly.The distribution of Cx40,Cx43 in myocardium of SHR+NaHS group is more regular than that of SHR group.Western blotting analysis showed that the expression of Cx40,Cx43,α-SMA,OPN in SHR group was increased when compared with those in WKY group(P<0.05),which was reversed in SHR+NaHS group(P<0.05).Conclusions H2S may reverse SHR induced myocardial remodeling through mediation of Cx40 and Cx43.