曲匹地尔对培养大鼠血管平滑肌细胞的有丝分裂素激活蛋白激酶(MAPK)和P34~(cdc2)激酶的影响

目的：研究曲匹地尔（Ｔｒａ）对培养大鼠主动脉血管平滑肌细胞的细胞增殖周期及对有丝分裂素激活蛋白激酶（ＭＡＰＫ）和Ｐ３４ｃｄｃ２激酶的表达及活性的影响。方法：以流式细胞术测定细胞周期，免疫印迹法测定ＭＡＰＫ和Ｐ３４ｃｄｃ２的表达，免疫沉淀后测定ＭＡＰＫ和Ｐ３４ｃｄｃ２对其特异性底物髓脂质碱性蛋白（ＭＢＰ）和ＨｉｓｔｏｎｅＨ１的磷酸化活性。结果：Ｔｒａ降低细胞周期中Ｓ期比例和细胞分裂增殖指数，能明显抑制给血清刺激后ＭＡＰＫ的表达和活性，明显抑制Ｐ３４ｃｄｃ２激酶活性而对其表达无明显影响。结论：Ｔｒａ对细胞周期的影响与其抑制ＭＡＰＫ和Ｐ３４ｃｄｃ２激酶活性和ＭＡＰＫ的蛋白表达有关。

EFFECTS OF TRAPIDIL ON EXPRESSION AND ACTIVITIES OFMITOGENACTIVATED PROTEIN KINASE(MAPK) AND P34cdc2 KINASE IN CULTURED RAT AORTIC SMOOTH MUSCLE CELLS

AIM: To study the effects of trapidil on cell cycle of cultured rat aortic vascular smooth muscle cells (VSMC) and on the expression and activities of mitogenactivated protein kinase (MAPK) and P34cdc2 kinase in cultured cells. METHODS: The cell cycle distribution was measured by flow cytometry. The expression of MAPK and P34cdc2 were assayed by Westernblotting. MAPK activity and P34cdc2 activity were assayed by phosphorylation of their specific substrates myelin basic protein (MBP) and Histone H1 after immunoprecipitation. RESULTS: Pretreatment with trapidil(Tra), the S phase in the cell cycle distribution and the mitotically active stage of the cells were markedly decreased. The enhancement of MAPK expression was markedly suppressed by Tra, but the expression of P34cdc2 was not affected by Tra. The MAPK and P34cdc2 activities were inhibited by Tra. CONCLUSION: Tra affects cell cycle by its inhibitory effect on the kinase activities of MAPK and P34cdc2, and its inhibitory effect on the expression of MAPK.