趋化素样因子1在大鼠主动脉损伤模型中的表达

Expression of chemokine-like factor 1 in balloon injured rat aorta

目的探讨趋化素样因子1在动脉内膜增生病变中的作用。方法雄性SD大鼠85只，随机分组，损伤模型分为8组，每组10只，球囊损伤法建立腹主动脉球曩损伤模型，分别在术后12h，1、3d，1、2、4、6、8周取材。对照组5只，接受假手术。测量内膜面积／中膜面积评估术后内膜增生程度；免疫组织化学法检测CKLF1蛋白水平的表达，IPP6．0测定阳性染色平均光密度作为评价指标；RT—PCR检测趋化素样因子1（CKLFI）在mRNA水平的表达，以B—aetin表达作为内参，CKLF1／β—actin比值作为CKLF1相对表达量。结果术后1周可见明显新生内膜形成，至术后4周内膜面积／中膜面积升高最明显，此后呈消退趋势，但仍明显高于术后1周及对照；免疫组化检测显示CKLF1在新生内膜表达强度高于中膜（P=0．016），新生内膜中CKLF1表达在术后1周较高；RT—PCR检测发现CKLF1表达在术后3d出现高峰，逐渐减退，但仍高于基础水平（P〈0．05）；内膜增生程度与CKLF1相对表达量呈正相关（R=0．70），但无统计学意义（P=0．188）。结论动脉损伤后趋化素样因子1表达上调，新生内膜中表达强度明显高于中膜组织，推测趋化素样因子1对内膜增生的发展可能起一定作用。

Objective To investigate the expression of chemokine-like factor 1 （CKLF1） in the balloon injured aorta of Sprague-Dawley rats. Methods Balloon expansion induced aorta injury model was established in 80 male Sprague-Dawley rats. Model rats were randomly divided into 8 groups. Rats were sacrificed at the postoperative periods of 12 hours, 1 day, 3 days, 1 week, 2 weeks, 4 weeks, 6 weeks, and 8 weeks respectively. Sham injury operation was applied to 5 rats as control. The ratio of intimal area （IA） and medial area （ MA ） was calculated to determine the extent of neointimal hyperplasia. Expression of CKLFI was examined at protein level with immunohistochemistry and at mRNA level with RT-PCR. Software IPP6. 0 was used to examine the mean optical density of positive staining. With β-actin expression as an internal control, semi-quantity of CKLF1 expression was calculated by CKLF1/β-actin. Results Visible neointima was noticed at 1 week postoperation. Extend of intimal hyperplasia （IA/MA） was most remarkable at 4 weeks and receded afterwards. Immnohistochemistry study showed that expression of CKLF1 was stronger in the neointima than in the media （P = 0. 016 ）. The expression was most obvious in the neotima at 1 week postoperation. RT-PCR showed peak expression at 3 days postoperation and declined gradually but still at a higher level than control （ P 〈 0. 05 ）. The extent of intimal hyperplasia （ IA/MA ） was positively correlated to the expression of CKLF1 （R = 0. 70, P = 0. 188）. Conclusion The expression of CKLF1 was up regulated in balloon injured rat aorta. The expression was more obvious in the neointima than in the media. CKLFI may play a role in the development of intimal hyperplasia.