ORC1与大鼠血管平滑肌细胞DNA复制的关系及意义探讨

Significance of ORC1 during the DNA replication of rat vascular smooth muscle cells

目的 探讨大鼠血管平滑肌细胞（vascular smooth muscle cells，VSMCs）增殖过程中DNA复制与起始识别复合物1（origin recognition complex 1，ORC1）基因表达的关系及意义。方法 采用组织块贴片法培养大鼠胸主动脉VSMCs，利用MTT法绘制生长曲线，分析不同生长状态VSMCs的DNA合成与ORClmRNA和蛋白表达的关系。结果 静止状态的VSMCs无ORC1 mRNA及蛋白质表达，血清刺激后12—24hVSMCsDNA的合成量显著增加，ORC1 mRNA及蛋白质表达量与VSMCs DNA的合成量相一致。结论 ORC1与大鼠VSMCs增殖过程中的DNA复制密切相关。

Objective To explore the expression of origin recognition complex 1 （ ORC 1 ） during DNA replication progress of rat vascular muscle ceils （VSMCs）. Methods VSMCs of rat thoracic aorta were obtained by the adherence method of tissue culture. The growth curve was drawn by MTT. The association between DNA replication and the expression of ORC1 mRNA and protein in different growth phases of VSMCs was analyzed. Results The expression of ORC1 mRNA and protein in quiescence stage of VSMCs was not found. After stimulated with serum, the expression of ORC1 mRNA in rat VSMCs increased significantly, peaked at 12 -24 h. The expression of ORC1 protein was similar to ORC1 mRNA in VSMCs. Meanwhile, the higher DNA replication of stimulated VSMCs was observed, peaked at 12 -24 h after serum addition. Conclusion ORC1 may be involved in the DNA replication of rat VSMCs during the progress of proliferation.