摘要
目的建立去势雌干眼症动物模型并探讨干眼症模型鼠角膜上皮细胞凋亡、相关基因表达与组织损伤的关系。方法将20只雌鼠随机分为去势雌及对照两组,每组10只。分别于手术前和手术后2、3、4、5、6个月行Schirmer试验、泪膜破裂时间(BUT)及角膜荧光素染色检测,并检测手术前后血清雌二醇水平。6个月后处死动物,取角膜进行组织病理学观察,并检测角膜上皮细胞中的bax、bcl-2等相关基因蛋白的表达。结果术后第9d去势雌组血清雌二醇水平(16.34±3.15)pg/mL明显低于对照组(44.39±4.03)pg/mL(P<0.01)。角膜上皮细胞中bax阳性表达的细胞数明显高于对照组(P<0.01);bcl-2阳性表达的细胞数明显低于对照组(P<0.01)。结论去势后雌鼠雌二醇水平明显低下,角膜上皮细胞中bax增加及bcl-2减少均与促进细胞凋亡有关,可能是导致组织学改变进而功能丧失引起干眼症的原因之一。
Objective Xerophthalmia is a multiple factor disease. Any causation of tear film and ocular surface dysfunction can induce xerophthalmia. This study was to establish a xerophthalmia model of estrogen-deficiency in rat and study the expression of apoptosis relevant genes in epithelial cells of corneas in xerophthalmia models. Methods Xerophthalmia model was created by extraction of ovary in 10 female rats,and 10 normal female rats served as controls. Schirmer test, tear film break-up time（BUT） and corneal fluorescence staining were performed before operation and 2,3,4,5 and 6 months after operation. Estrogen level before and after operation was detected by chemiluminescence. The corneal tissues were obtained 6 months after modeling for histological observation under the optical microscope and transmission electron microscope. The expression of bax and bcl-2 in corneal samples were investigated by immunohistochemical staining. Results Compared with control group, Schirmer test and BUT were significantly lower in model group in 5 months after operation, suggesting a statistically significant difference （ P 〈 0.01 ）. Corneal fluorescence staining showed positive results in model group 4 months later. The estrogen level in rat blood serum after operation was （ 16.34 ± 3.15 ） pg/ml, showing a significantly decrease compared with before operation （44.39 ± 4.03 ） pg/ml （ P 〈 0.01 ）. The pathological examination of the xerophthalmia models exhibited an irregular muhilayer change. Endoplast breakage, mitochondria swelling and microvilli desquamation were seen in xerophthalmia models. The cell numbers expressing bax in corneal epithelium were 483.29 ± 214. 27 in xerophthalmia models and 232.57 ± 119. 24 in control group, showing a significant difference （ P 〈 0. 01 ）. However, the cell numbers expressing bcl-2 were 264.12 ± 101.33 in xerophthalmia models, indicating an evident decrease in comparison with control group（480. 35 ± 153. 01 ） （P 〈 0. 01 ）. Conclusion The estrogen level in blood serum is significantly lower in xerophthalmia model rat. The apoptosis of corneal epithelial cells may be one of mechanisms leading to the destruction in xerophthalmia. Bax may promote cell apoptosis,but bcl-2 inhabits apoptosis procedure.
出处
《眼科研究》
CSCD
北大核心
2007年第11期814-817,共4页
Chinese Ophthalmic Research
作者简介
通讯作者：王传富（Email：wangchuanfu1942@hotmail．com）
