目的：通过比较C x 43在正常大鼠和自发性高血压大鼠胸主动脉表达的差异，以及经卡托普利干预后的变化，来阐明卡托普利抗高血压血管重构的分子机制。方法：12周龄自发性高血压大鼠（SHRs）16只随机分为对照组和卡托普利干预组，以年龄和体重匹配的Wistar‐Kyoto大鼠（WKYs）为正常空白对照组。干预组，灌胃法给予卡托普利[12．5mg · d）]，8周后，采用无创血压测定仪测量3组大鼠尾动脉收缩压；用酶联免疫吸附法测量血浆和胸主动脉组织血管紧张素Ⅱ（AngII）浓度。采用实时定量RT‐PCR和Western blot分析，检测3组大鼠胸主动脉组织内Cx43的mRNA及蛋白表达。结果：SHR组的血浆、动脉组织AngII浓度较WKY 大鼠组明显升高，而卡托普利干预组的血浆、组织AngII浓度则较SHR组明显降低。SHR组胸主动脉的Cx43的mR‐NA表达高于WKY组（P＜0．01），卡托普利降低Cx43mRNA的表达（P＜0．01）。蛋白印迹法显示，SHR组大鼠胸主动脉中，Cx43蛋白表达高于WKY大鼠组（P＜0．01）。卡托普利降低组织主动脉内Cx43的蛋白表达（ P＜0．01）。结论：自发性高血压大鼠主动脉Cx43表达增强，卡托普利能够降低胸主动脉Cx43的表达。%Objective:To investigate the differential expression of connexin 43 in thoracic aorta between spontaneously hypertensive rats(SHRs)and Wistar‐Kyoto rats(WKYs) ,and effects of captopril on the expression of Cx43 in thoracic aorta of SHR and possible underlying mechanism .Methods:Sixteen 12‐weeks old male SHRs were randomly divided into two groups:SHR control group receiving placebo and captopril group receiving captopril 12 . 5mg/(kg · d) .Another eight WKY rats served as blank control group .Before and after eight weeks treatment ,rats arterial pressure of tail were measured .When the treatment finished ,plasma angiotensin II level and thoracic aortic tissue angiotensin II level were measured with enzyme linked immunosorbent assay (ELISA ) method .Moreover , Cx43 mRNA and protein levels in thoracic aortic tissue were determined by RT‐PCR and Western blot .Results:The plasma and thoracic aortic tissue angiotensin II levels were significantly increased in SHR as compared with the WKY group and captopril reduced the plasma and thoracic aortic tissue angiotensin II as compared with the SHR group(P<0 .01) .The expression of Cx43 mRNA in thoracic aorta of SHR group was obviously higher than that in the WKY rats(P<0 .01)and was markedly decreased by captopril treatment(P<0 .01) .Cx43 protein level was higher as com‐pared with that in WKY rats(P<0 .01) .Treatment with captopril significantly down‐regulated Cx43 protein expres‐sion(P<0 .01) .Conclusion:The expression of Cx43 up‐regulated in thoracic aorta of SHR and captopril treatment can ameliorate Cx43 increasing in thoracic aorta of SHR .
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