大鼠颈动脉气囊导管损伤早期原癌基因c-Fos、c-Jun的表达研究

Proto-oncogene c-fos、c-jun expression in arterial wall early after balloon injury

目的：采用ＲＴ－ＰＣＲ方法研究动脉损伤早期原癌基因ｃ－ｆｏｓ、ｃ－ｊｕｎ的表达规律；方法：制备大鼠颈动脉气囊导管扩张损伤模型，采用ＲＴ－ＰＣＲ方法检测损伤早期不同时相点动脉壁平滑肌细胞（ＶＳＭＣ）ｃ－ｆｏｓ、ｃ－ｊｕｎ基因的表达丰度，同时采用免疫组化方法观测ｃ－ｆｏｓ蛋白的表达。结果： ｃ－ｊｕｎ在损伤后３０ｍｉｎ达高峰。术后１ｈ、２ｈ仍能检测到明显的表达，术后５ｈ后不能检出。ｃ－ｆｏｓ在术后３０ｍｉｎ、１ｈ均可检测到该基因多量的表达，以后随时间的推移表达逐渐下降，５ｈ时不能检出。损伤后４５ ｍｉｎ中膜残留ＶＳＭＣ ｃ－ｆｏｓ蛋白表达阳性，阳性率８６％。结论：在动脉损伤后极早期即有ｃ－ｆｏｓ、ｃ－ｊｕｎ的大量表达，ＲＴ－ＰＣＲ检测原癌基因的表达为研究动脉损伤早期ＶＳＭＣ的活化机理提供了一个的敏感方法。

Objective:To study the expression of proto-oncogene c-fos、c-jun in arterial wall during the early period after balloon injury. Methods: The balloon catheter injury was performed on left common carotid of rat by imitating the process of angioplasty. Total RNA was isolated from the arterial wall at different time after injury. Expression of c-fos、c-jun mRNA was demonstrated and levels of two mRNA were estimated by the reverse transcriptase-polymerase chain reaction (RT-PCR). Meanwhile, presence of c-fos protein in vascular smooth muscle cells (VSMCs) was detected with immunohistochemistry. Results: The expression of c-jun reached its maximum 30 min after injury and remained elevated at 1 and 2 hour. c-fos level was maximal at 0.5 h and maintained for 1 hour. Afterwards it gradually declined and returned to basal levels after 5 h. Immunostain of c-fos protein was mostly positive in the remaining VSMCs at 45 min ( 86% ). Conclusion: Balloon injury induces high expression of c-fos and c-jun in the very early period. Using RT-PCR to detect proto-oncogene expression provides a sensitive method for studying the principle of VSMCs activition and proliferation during the early period after injury.