雌二醇对萘处理卵巢切除雌性大鼠晶状体形态结构的影响

The effect of estradiol on morphology of lens in ovariectomized female rats trea-ted with naphthalene

目的:观察雌二醇对萘处理卵巢切除雌性大鼠晶状体细胞及组织形态结构的影响,探讨雌二醇对大鼠晶状体保护作用的形态学机制。方法:健康雌性、性成熟SD大鼠32只随机分为4组:卵巢切除组、卵巢切除+雌二醇组(雌二醇组)、卵巢切除+雌二醇和孕酮组(雌二醇+孕酮组)、正常对照组。术后2wk起各组均用300g/L萘混悬液灌胃(0.5g/Kgbw,2次/wk),肉眼和裂隙灯显微镜观察各组大鼠晶状体变化。灌胃6wk后处死大鼠,用放免法检测血清中雌二醇和孕酮浓度,取其晶状体分别进行光镜下组织细胞的形态观察,扫描电镜下晶状体纤维厚度及指突数的测定。结果:裂隙灯显微镜下,各组均有不同数量的大鼠晶状体出现空泡、小水裂以及前囊点状混浊,但各组间差异无显著性。光镜下,卵巢切除组表现出较其他三组更重的细胞和组织损害严重,而雌二醇组以及雌二醇+孕酮组则与正常组对照组表现相似。扫描电镜下,卵巢切除组晶状体纤维厚度较正常组增加(P<0.01),指突数较正常组少(P<0.01),而雌二醇组和雌二醇+孕酮组两项指标均与正常组接近。结论:雌二醇可能通过维持晶状体囊膜及晶状体上皮细胞正常结构,防止晶状体上皮细胞增殖,减轻晶状体皮质纤维细胞水肿,维持细胞连接的形态和数量,维持晶状体皮质纤维细胞的规则有序排列等途径发挥其对晶状体的保护作用。

AIM： To investigate the effect of estradiol on morphology of lens in ovariectomized female rats treated with naphthalene, and explore the morphological mechanism of protective effects of estradiol on rats＇lens. METHODS： Thirty-two female Sprague-Dawley rats were randomly divided into four groups： ovariectomy, ovariectomy with estradiol replacement therapy, ovariectomy with estradiol and progesterone replacement therapy, and normal. After 2 weeks of operation, each group was given 300g/L naphthalene （0. 5g/kg body weight, twice a week） for 6 weeks through a stomach tube. The changes of the lenses were observed with naked eye and slit-lamp microscope. After 6 weeks of naphthalene administration, all rats were killed and their serum estradiol and progesterone concentration were determined with radioimmunoassay. The lenses were taken out to observe morphological changes of the cells and structure under the light microscope. The thickness of lens fibers and the numbers of lens fibers were measured under the scanning electron microscope. RESULTS： Under the slit-lamp microscope, different number of rats lens with symptoms like vacuoles, clefts and punctate opacity were found in every group, but without significant differences in these symptoms. Under the light microscope, ovariectomy group showed serious injury in morphology and structure of cell and tissue compared with normal group, but the estradiol group, estradiol and progesterone group showed similar results with normal group. Under the scanning electron microscope, the thickness of lens fiber in ovariectomy group was larger than in normal group（P〈0.05）, and the numbers of lens fibers were less than in normal group （P〈 0.01）, but both of them in estradiol group, estradiol and progesterone group were found similar with normal group. CONCLUSION ： The protective effect of estradiol on lens may be performed through maintaining the normal morphology and structure of LC, LECs, and LCFCs, preventing proliferation of LECs, reducing hydropsia of LCFCs, remaining the shape and numbers of cell junctions, and keeping regular arrangement of LCFCs.