中文摘要：

目的 观察血小板源性生长因子-BB（PDGF-BB）对大鼠血管平滑肌细胞（VSMC）的增殖及其ras蛋白表达的影响.方法 体外培养大鼠VSMC并传代,将第4代VSMC分4组,设空白对照组,另设3组分别加入1、2、4 μg/L PDGF-BB进行干预,采用细胞计数、免疫组织化学及免疫荧光等方法,观察干预后1、3、7 d 3个时间点的VSMC计数、增殖细胞核抗原（PCNA）表达及相应时段ras蛋白的表达,并分析两者之间的相关性.结果 （1）在7 d内各组VSMC计数均逐渐增加,其中2 μg/L和4 μg/L PDGF-BB组的计数增长较对照组快（P＜0.05）,4 μg/L PDGF-BB组较1 μg/LPDGF-BB组快（P＜0.05） （2）免疫组织化学和免疫荧光检测显示,干预3 d后各组VSMC增殖细胞百分比均表现为高PDGF-BB浓度组高于低浓度组（P＜0.05）,ras蛋白荧光表达强度亦呈现相同趋势（P＜0.01）.PDGF-BB干预后的VSMC的PCNA表达和ras蛋白表达呈显著正相关（r=0.735,P＜0.05）.结论 PDGF-BB可以刺激体外培养大鼠VSMC增殖,并可促进其ras蛋白的表达.

英文摘要：

Objective To investigate the impact of platelet derived growth factor-BB （PDGF-BB）on in vitro cultured rat vascular smooth muscle cell （VSMC） proliferation and its ras protein expression.Methods VSMCs were obtained from SD rat weighing about 200 g and cultured in vitro. After subculture for three times, VSMCs were transferred into 24-hole culture plate and divided into four groups： control group, and three experimental groups intervened with concentrations of 1, 2 and 4 μg/L PDGF-BB. The proliferation, ras protein expression of VSMCs and the correlation between the two indexes were evaluated by cell counting, immunohistochemical and immunofluorescence methods respectively at 3 time points： 1st,3rd and 7th day. Results （ 1 ） Within 7 days, VSMCs were increased gradually in all 4 groups. The cell count in 2 μg/L and 4 μg/L PDGF-BB groups was increased more faster than in control group, and that in 4 μg/L LDGF-BB group was increased more faster than 1 μg/L LDFG-BB group （P 〈0.05）. （2） Immunostaining and immunofluorescence showed that proliferation cell nuclear （PCNA） expression of VSMCs in higher concentration PDGF-BB group was significantly higher than in lower concentration PDGF-BB group （ P 〈 0.05 ） after intervention for 3 days. A likewise trend could be detected in ras protein expression of VSMCs （ P 〈 0.01 ）. The expression of ras protein in VSMCs was significantly positive correlation with that of PCNA （ r = 0.735, P 〈 0.05 ）. Conclusion PDGF-BB stimulates the proliferation of in vitro cultured rat VSMCs and increases its ras protein expression.