雌二醇对大鼠颈动脉球囊损伤后血管平滑肌细胞增殖和内皮功能的影响

目的 研究雌二醇对血管内皮损伤后血管壁细胞增生和内皮功能恢复的作用。方法 应用球囊导管剥脱大鼠的左颈总动脉,于术前六天和术后两周给予17-β雌二醇,通过形态学分析和免疫组化测定血管内膜增生和血管平滑肌细胞增殖程度,并测定乙酰胆碱诱导的内皮依赖性血管舒张反应。结果 17-β雌二醇显著抑制血管内皮损伤后平滑肌细胞增殖和减少新生内膜面积。内皮损伤后乙酰胆碱诱导的血管舒张反应显著降低,最大为12%±6%;雌二醇能使其显著改善,最大舒张反应为48%±9%(P<0.05)。结论 雌二醇显著抑制血管内皮损伤后平滑肌细胞增殖和促进内皮功能的恢复。

Effects of estrogen on intimal thickening and impairment of vascular function after carotidinjury in rats

Aim Effects of estrogen on theproliferation of vascularsmooth muscle cells and theimpairment of endon thelium-d epentment vascularrela xation after vascular injury were studied.Methods Ovariectomized Wistar rats wererandomly dividedinto two subgroups treated with either 17βestradiol or vehicle and were subjected to balloon injury of theleft common carot id artery.Two weeks later, thedeg rees of myointimal thickening and proliferation of vascularsmooth muscle cells (VSMC)were evaluated by morphometric analysis and immunostained against proliferating cellular neuclear antigen (PCNA).Acety lcholine-induced endon thelium-depende ntrelax ation was measured.Results 17βestradiol signi ficantly inhibited theproliferation of VSMC (P<0.05)and attenuated neointimal area (P<0.05). Acety lcholine-induced endon thelium-dependentrelax ation was greatly reducedin injured arteries, with themax imal relax ation being 12 %±6 %.Estradiol ameliorated signif icantly theimpairment of vascularrelaxation, with themaximal relax ation being 48 %±9 %.Conclusion Estradiol can inhibitsmoo th muscle proliferation and ameliorate thedecrease in endon thelial-dependentrelax ation after balloon injury.