雌激素对大鼠趋化因子受体CXCR2表达的影响：动脉粥样硬化的指征

目的：研究17β-雌二醇对体内单核细胞趋化因子受体CXCR2表达的影响．方法：流式细胞仪测定单核细胞趋化因子受体CXCR2的蛋白表达、逆转录PCR测定其mRNA水平．结果：在卵巢完整和切除卵巢的大鼠中,喂养富含胆固醇饮食6周增加单核细胞趋化因子受体CXCR2 mRNA和蛋白水平．在切除卵巢的大鼠,注射17β-雌二醇(5和20μg．kg^-1．d^-1)显著减少了胆固醇诱导的CXCR2 mRNA及蛋白表达的增加．正常饮食的大鼠,切除卵巢增加了趋化因子受体CXCR2 mRNA和蛋白水平的表达,但是注射17β-雌二醇可以防止它表达的增加．结论：生理性浓度的雌激素调节基础及胆固醇诱导的趋化因子受体CXCR2表达．

Effect of estradiol on chemokine receptor CXCR2 expression in rats: implications for atherosclerosis

AIM: To study the effect of 17beta-estradiol on expression of chemokine receptor CXCR2 in monocytes in vivo. METHODS: Expressions of chemokine receptor CXCR2 mRNA and protein were measured by RT-PCR and flow cytometry, respectively. RESULTS: In both ovary-intact and ovariectomized (OVX) rats, CXCR2 protein and mRNA expression were significantly increased in rats fed with a high-cholesterol diet for 6 weeks. The cholesterol-induced increases in CXCR2 protein and mRNA expression were significantly attenuated in OVX rats injected with estradiol-17beta (17beta-E2) (5 and 20 microg x kg(-1) x d(-1)). In normal diet rats, CXCR2 protein and mRNA expression were increased in OVX rats compared with ovary-intact rats, and this increase was prevented by 17beta-E2. CONCLUSION: Both basal and hypercholesterolemia-induced increases in chemokine receptor CXCR2 are modulated by physiological concentrations of estradiol.