葛根素对小鼠长骨雌激素受体α(ERα)表达的影响

Regulation of the expression of estrogen receptor alpha(ERα) of epiphysis of mouse in vitro with puerarin

目的:研究葛根素对长骨骺板雌激素受体亚型ERα分布及含量的影响,并与内源性雌激素作用相比较,探讨葛根素对骨的作用机制。方法:取16 d胎龄雌性小鼠前肢尺骨,置于BGJb培养基中,葛根素(10-6,10-5和10-4 mol·L-1)和雌二醇(10-6 mol·L-1)作用48 h后固定脱钙,HE染色,光镜下计数骨干破骨细胞数及肥大区软骨细胞数;免疫组织化学染色,光镜下观察阳性细胞定位,图像分析系统下测定免疫反应阳性细胞数和阳性细胞面积。结果:葛根素组及雌二醇组与空白对照组相比软骨均增粗、变长,静止区、增殖区和肥大区细胞数目增多,骨化区破骨细胞数量减少。空白对照组骺板肥大区有ERα免疫反应阳性的软骨细胞,表达较弱,静止区、增殖区几乎没有表达。经葛根素或10-6 mol·L-1的雌二醇作用48 h后,与空白对照组相比,肥大区表达明显增强,静止区、增殖区也均有ERα表达,葛根素作用明显弱于雌二醇。结论:葛根素能够促进软骨内成骨,其作用可能与其上调ERα的表达有关。

Objective：To evaluate the effect and gen on the distribution and the expression of estrogen mechanism of puerarin receptor alpha （ ERa ） versus endogenous estroin fetal mice epiphyseal growth plate. Methods ：The long bone of forelimbs of female fetal mice at age of 16-day gestation were free of muscles and soft tissues and then cultured for 48 h in BGJb media together with estradiol（ 10^-6 mol·L^ - 1 ） and purearin（ 10^-6,10^-5 or 10^-4 mol·L^-1） , respectively. Subsequently, the slices from mid-longitudinal sections of the bones free of calcium were fixed up and stained with HE dying to analyze the numbers of osteoclasts and hypertrophic chondrocytes under biological microscope. The ERα proteins in epiphyseal plate were assayed by immunohistochemical procedure. The number and area of receptor-positive cells in the resting, proliferative and hypertrophic zones of the epiphyseal plate were measured using an image analytic system. Results：The blank ERα had insignificant expressions in hypertrophic zone and no positive cells in the resting and proliferative zones. After cultured with puerarin or estradiol 10^-6 mol· L^-1 for 48 h, the ERa significantly showed hyperplasia in hypertrophic zone and the positive cells in the resting and proliferative zones. The ERα response with estradiol was superior to the one with puerarin. Conclusion：Puerarin improved the bone growth of mice by up-regulating the expression of ERα.