全反式维甲酸对兔颈动脉粥样硬化模型内膜增殖的影响

①目的观察全反式维甲酸（ATRA）对兔颈动脉粥样硬化模型内膜增殖的影响。②方法36只新西兰大白兔随机分为假手术组、对照组和ATRA治疗组；假手术组给予高脂饮食但手术不损伤颈动脉内膜，余操作同对照组；对照组给予高脂饮食加空气干燥损伤颈动脉内膜；ATRA治疗组在高脂饮食加空气干燥损伤颈动脉内膜的同时给予ATRA治疗，内膜损伤后1周和4周观察平滑肌细胞中增殖细胞核抗原（PCNA）和细胞周期素E（cyclin E）的表达及兔颈动脉内膜增殖的情况。③结果ATRA治疗组平滑肌细胞中的PCNA和cyclin E的表达较对照组明显减弱（F=7．65～8．89，q=4．27～10．33，P〈0．05、0．01）；颈总动脉病变也较对照组轻微（t=4．330～5．042，P〈0．01）。④结论ATRA能抑制兔颈动脉内膜损伤后内膜增殖，其机制可能为通过抑制cyclin E的表达而抑制平滑肌细胞的增殖。

EFFECTS OF ATRA ON INTIMAL PROLIFERATION IN INJURED CAROTID ARTERY IN RABBITS

Objective To examine the effects of ATRA on post-injury intima of rabbit carotid artery. Methods Thirty-six rabbits were randomly divided into three groups, sham-operation group, control group and ATRA-treated group. The rabbits in the sham-operation group were fed with cholesterol-enriched diet but their carotid artery intima were not injured; those in the control group were fed with cholesterol-enriched diet and their carotid artery intima were injured; those in the ATRA-treated group were fed with cholesterol-enriched diet supplemented by ATRA for four weeks and their carotid artery intima were iniured.The carotid arteries were harvested for histomorphometry observation and PCNA and cyclin E immunohistochemistry analysis one and four weeks after the operation. Results ATRA decreased atherosclerotic lesion in rabbits carotid artery intima and the expression of PCNA and cyclin E in smooth muscle cells. Conclusion ATRA treatment can inhibit atherosclerotic progression by inhibiting the proliferation of vascular smooth muscle cells. The mechanism may be related to inhibition of cyclin E in vascular smooth muscle cells.