反义凝血酶受体基因表达对猪主动脉平滑肌细胞增殖的抑制作用

目的寻找抑制血管损伤后血管内皮增生的有效方法以预防介入治疗后再狭窄的发生。方法利用重组ＤＮＡ技术构建了含有部分反义凝血酶受体（ＡＴＲ）ｃＤＮＡ片段的真核表达质粒ｐｃＤＮＡ３／ＡＴＲ，应用超大球囊损伤及高胆固醇饲喂法建立了小型猪主动脉内皮损伤模型并培养了其主动脉平滑肌细胞（ＡＳＭＣ），通过３Ｈ－ＴｄＲ掺入及Ｎｏｒｔｈｅｒｎｂｌｏｔ观察ＡＴＲ的表达对猪ＡＳＭＣ增殖及生长因子基因表达的影响。结果ＡＴＲ基因的稳定表达：（１）能抑制ＡＳＭＣ的ＤＮＡ合成（正常猪ＡＳＭＣＤＮＡ合成下降４１．８％，而内皮损伤血管下降５０３％）；（２）能从ｍＲＮＡ及蛋白水平抑制ＡＳＭＣ凝血酶受体基因的表达；（３）能使猪ＡＳＭＣ中ＰＤＧＦＡ链及ｂＦＧＦ的表达明显降低。结论ＡＴＲ可有效地抑制猪ＡＳＭＣ的增殖与凝血酶受体所介导的细胞内信号传导有关。

The inhibiting effect of antisense thrombin receptor gene on the proliferation of pig vascular smooth muscle cell

Objective To search for an effective approach to prevent the formation of restenosis after angioplasty. Methods A recombinant eukaryotic expression plasmid vector containing partial antisense thrombin receptor (ATR) gene named pcDNA3/ATR was constructed using recombinant DNA technique. Minipig aorta injury model was established by oversized balloon catheter combined with high cholesterol diet feeding and its aortic smooth muscle cells(ASMC) were cultured. The effect of ATR gene expression in mini pig ASMC proliferation and growth factor gene expression were studied by 3 HTdR incorporation and Northern blot. Results The DNA synthesis in pig ASMC could be inhibited by ATR gene expression ( The DNA synthesis in normal ASMC was lowered by 41.8%, and that in ASMC from injured artery was lowered by (50.3%). The mRNA and protein synthesis of TR could be downregulated by ATR gene expression. The mRNA expression of PDGFA chain and bFGF stimulated by fetal calf serum (FCS) with thrombin were both downregulated in pig ASMC with expressed ATR gene. Conclusion ATR gene expression can inhibit the proliferation of pig ASMC, and this is induced by its inhibiting effect on TR and finaly the signal transduction in ASMC.