医学论文范文:17β_雌二醇对新生牛血清诱导的血管平滑肌细胞增殖反应的影响及其机制
【摘要】 目的:探讨雌甾_1,3,5(10)_三烯_3,17β_二醇(17β_雌二醇)对新生牛血清诱导血管平滑肌细胞(VSMCs)增殖反应的影响及其机制。方法:用新生牛血清刺激培养的VSMCs增殖,MTT法检测17β_雌二醇对新生牛血清诱导的VSMCs增殖的影响,并用Western blot检测caveolin_1蛋白,诱导型一氧化氮合酶(iNOS)及NO在此过程中的变化。结果:与对照组比,新生牛血清可促进VSMCs增殖(P<0.05),17β_雌二醇作用24h后能明显抑制上述作用(P<0.05);17β_雌二醇预处理可抑制新生牛血清诱导的VSMCs中caveolin_1,iNOS蛋白表达下降及NO释放(P<0.05);17β_雌二醇受体阻断剂1_{4_[2_(n,n_二甲氨基)乙氧基]苯}_1,2_二苯_1_丁烯(他莫昔芬)预处理可部分逆转17β_雌二醇的抑制作用(P<0.05)。结论:17β_雌二醇通过其受体可抑制新生牛血清诱导的VSMCs增殖,此过程与上调caveolin_1蛋白表达,激活iNOS,增加NO释放有关。
【关键词】 17β_雌二醇;caveolin_1;诱导型一氧化氮合酶;血管平滑肌细胞
Influence of 17β_estradiol on Vascular Smooth Muscle Cells Proliferation Induced
by Fetal Calf Serum and Its MechanismLIU Hai_mei1,ZHAO Xiao_feng2,XU Jin_wen3,LIN Gui_ping3,WANG Ting_huai3
(1 Department of Physiology,Guangzhou University of Chinese Medicine,Guangzhou 510006,China,2 Department of Physiology,Me_dical College of Shaoguan University,Shaoguan 512026,China,3 Department of Physiology,Zhongshan Medical College,Sun_Yat Sen University,Guangzhou 510080,China)
[Abstract]Objective: To investigate the influence of 17β_estradiol on vascular smooth muscle cells(VSMCs)proliferation induced by fetal calf serum and the related mechanism. Methods: The fetal calf serum was used to stimulate cultured VSMCs proliferation(P<0.05),and the effects of estrogen on VSMCs proliferation were determined by MTT,and the expressions of caveolin_1 and inducible nitric oxide synthase(iNOS)were also detected by Western blot. Results: Compared with the normal control group, the fetal calf serum could increase the VSMCs proliferation(P<0.05), and inhibit proliferation effect of fetal calf serum,pretreated with estradiol for 24 hours(P<0.05). Western bolt results further proved that 17β_estradiol inhibited the downregulation of caveolin_1, iNOS and NO induced by fetal calf serum, which was prevented by pretreatment with estrogen antagonist, Tamoxifen(P<0.05). Conclusion: 17β_estradiol can inhibit VSMCs proliferation induced by fetal calf serum, and this effect is mediated by estrogen receptor. 17β_estradiol increases caveolin_1 and iNOS protein expression, and NO release,leading to the inhibition of VSMCs proliferation induced by fetal calf serum医.学全.在.线网站www.lindalemus.com.
[Key Words]17β_estradiol,caveolin_1,inducible nitric oxide synthase,vascular smooth muscle cell
血管损伤后,刺激因子诱导的血管平滑肌细胞(VSMCs)的过度增殖和迁移是再狭窄发生的关键[1_2],临床及流行病学资料显示,雌甾_1,3,5(10)_三烯_3,17β_二醇(17β_雌二醇)具有心血管保护作用,我室前期的实验研究也证实这点[3],在离体培养的VSMCs中17β_雌二醇可抑制ET_1诱导的VSMCs增殖,此过程与抑制细胞外信号通路1/2(ERK1/2)有关。17β_雌二醇的血管保护作用与诱导NO生成有关,但在VSMCs中,17β_雌二醇通过何种途径诱导NO合成,目前尚未明了。因此,本研究利用离体培养的兔胸主动脉VSMCs,观察caveolin_1及诱导型一氧化氮合酶(iNOS)在17β_雌二醇诱导NO合成及抑制VSMCs增殖中的作用和机制。