原癌基因c-myc,c-fos在自发性高血压大鼠左心室的表达

Expression of Proto oncogenes c myc and c fos in Left Ventricle in Spontaneously Hypertensive Rats

探讨ＳＨＲ左心室肥厚时原癌基因ｃ－ｍｙｃ，ｃ－ｆｏｓ表达的变化及其意义。方法１６周龄的雄性ＳＨＲ在测量收缩压和体重后处死，年龄、性别和数量配对的正常血压的ＷＫＹ为对照组。取左心室称重，异硫氰酸胍酸－酚氯仿一步法提取组织总ＲＮＡ，用３２Ｐ标记的ｃ－ｍｙｃ，ｃ－ｆｏｓｃＤＮＡ探针行Ｎｏｒｔｈｅｒｎ杂交，同时取左心室组织制备蛋白抽提物进行Ｗｅｓｔｅｒｎ免疫印溃杂交以及免疫组织化学染色观察ｃ－ｍｙｃ，ｃ－ｆｏｓ细胞定位及表达量。结果ＳＨＲ左心室组织ｃ－ｍｙｃｍＲＮＡ及癌蛋白表达量均明显高于ＷＫＹ，ｃ－ｍｙｃ癌蛋白主要定位于心肌成纤维细胞核中，ｃ－ｆｏｓ表达在ＳＨＲ与ＷＫＹ之间，以及心肌细胞与成纤维细胞之间无差别。结论成纤维细胞ｃ－ｍｙｃ的表达增高对ＳＨＲ左心室肥厚发展与维持有重要意义。

Aim\ To determine the alteration and its significance of the expression of proto oncogenes c myc and c fos in the hypertrophied left ventricle of spontaneously hypertensive rats(SHR).\ Methods\ Male SHR and WKY were decapitated at 16 weeks old, systolic blood pressure and left ventricle mass to body weight ratio(LVM/BW) were measured.\ Level of c myc and c fos mRNA were determined by Northern blot, semiquantification and localization of oncoproteins c myc, c fos were analyzed by Western blot and immunohistochemical method.\ Results\ The level of both mRNA and oncoprotein of c myc in hypertrophied left ventricle were significantly higher than that of WKY; c myc oncoprotein was mainly located in the nuclei of cardiac fibroblasts.\ There were no differences of c fos expression in myocytes and fibroblasts between SHR and WKY.\ Conclusion\ These data strongly suggested that the expression of c myc in cardiac fibroblasts may play an important role in the development of left ventricle hypertrophy in SHR.