大鼠胸主动脉内膜损伤后血管中的基质Gla蛋白的mRNA动态表达及曲匹地尔对其的影响

目的研究大鼠胸主动脉内膜损伤后血管中的基质Ｇｌａ蛋白（ｍａｔｒｉｘＧｌａｐｒｏｔｅｉｎ，ＭＧＰ）ｍＲＮＡ动态表达及曲匹地尔（Ｔｒａ）对其的影响。方法在球囊剥脱大鼠主动脉内皮造成血管内膜损伤后１ｄ，７ｄ，１４ｄ和２１ｄ处死动物，以异硫氰酸胍一步法提取大鼠胸主动脉ｍＲＮＡ，用合成的两段针对基质Ｇｌａ蛋白基因的引物进行逆转录ＰＣＲ（ＲＴ－ＰＣＲ），同时以ＧＡＰＤＨ作为对照，检测血管中平滑肌细胞的ＭＧＰ的表达。结果血管损伤后的１ｄ，７ｄ和１４ｄ，ＭＧＰｍＲＮＡ的表达逐步升高，血管损伤后１４ｄ左右其表达开始降低。Ｔｒａ（４０ｍｇ·ｋｇ－１·ｄ－１，ｉｐ）在各个时间点均能明显阻抑该蛋白的ｍＲＮＡ的表达。结论血管内膜损伤后，ＭＧＰｍＲ－ＮＡ表达呈现先增高后降低的动态变化，Ｔｒａ抑制血管平滑肌细胞的表型转化及增殖可能与其抑制ＭＧＰｍＲＮＡ的表达有关。

Dynamic change of matrix Gla protein (MGP) mRNA expression in the healing process of rat thoracic aorta damaged by balloon angioplasty and effect of trapidil on the expression

AIM The dynamic change of matrix Gla protein (mGP) mRNA expression in the healing process of rats thoracic aorta damaged by balloon angioplasty and the effect of trapidil on the expression were investigated. METHODS Rats were killed l d, 7 d, 14 d and 21 d after rats thoracic aorta was damaged by balloon angioplasty. The total RNA of thoracic aorta was extracted by single step method of RNA isolation. Controlled by GAPDH, the mRNA of MGP was detected by RT PCR with two oligonucleotide primers spectific for rat sequences of MGP. RESULTS The expression of MGP in the thoracic aorta damaged group was higher compared with normal group. 1 d, 7 d and 14 d after thoracic aorta was damaged, the expression of MGP was increased gradually, and it was decreased after artery damaged 21 d. At above time points, MGP mPNA was significantly inhibited by 40 mg·kg -1 ·d -1 of trapidil. CONCLUSIONS The expression of MGP mRNA was increased at first, and then decreased after thoracic aorta was damaged. The mechanism that trapidil suppressed the phenotype transition and the proliferation of VSMC may involve the inhibitory effect on the expression of MGP.