蒙脱石滴眼液对小鼠泪膜功能和角膜上皮厚度的影响

目的　研究蒙脱石滴眼液对小鼠泪膜功能和角膜上皮厚度的影响。方法　将24只BALB/C小鼠随机分成A组和B组，每组12只。A组用15 g·L^-1蒙脱石混悬液滴眼，B组用等量PBS滴眼，每天3次。分别在滴眼前和滴眼后1 d、4 d、7 d对2组小鼠进行泪液分泌试验、泪膜破裂时间（break up time，BUT）检测和角膜荧光素（fluorescein，FL）染色评估，滴眼后7 d利用光学相干断层扫描血管造影（optical coherence tomography angiograph，OCTA）进行角膜分区，分别测量2组小鼠不同区域角膜上皮厚度。结果　A组与B组泪液分泌量有差别（F=19.731，P=0.009），A组较B组泪液分泌量低，泪液分泌破坏显著，且2组泪液分泌量的差别有随着处理时间延长逐渐变大的趋势；滴眼后4 d和7 d，两组泪液分泌量比较，差异均有统计学意义（t=3.847、5.695，P=0.026、0.009）。A组较B组BUT缩短（F=22.432，P=0.001），泪膜破坏明显，且2组泪膜破坏程度的差别随着处理时间延长而有变大的趋势，滴眼后4 d和7 d，两组BUT比较，差异均有统计学意义（t=5.753、5.695，P=0.024、0.009）。A组较B组角膜FL染色评分增加（F=14.753，P=0.003），角膜上皮细胞损伤明显，且2组角膜FL染色的差别有随着处理时间延长逐渐变大的趋势，滴眼后4 d和7 d，两组FL评分比较，差异均有统计学意义（t=7.536、9.864，P=0.031、0.012）。滴眼后7 d，与B组相比，A组各区域角膜上皮厚度均变厚，差异均有统计学意义（均为P＜0.05）。结论　蒙脱石滴眼液会破坏小鼠的泪液分泌功能和泪膜稳定性，并损伤小鼠角膜上皮细胞，使角膜上皮变薄。

Effects of montmorillonite eye drops on tear film function and corneal epithelial thickness

Objective　To study the effects of montmorillonite eye drops on tear film function and corneal epithelial thickness.Methods　Twenty-four BALB/C male mice were selected in this study and divided into two groups randomly and they were A group (12 mice) and B group(12 mice).The A group was given 15 g·L^-1 montmorillonite eye drops thrice a day,while the B group was given PBS drops.The Schirmer Ⅰ test,tear film break-up time (BUT) and fluorescein stain of corneal epithelium (FL) were conducted on day 1,4,7 after dropping eyes.The optical coherence tomography angiography (OCTA) was conducted on day 7 after dropping eyes to zone corneas before measuring corneal epithelial thickness of these corneal zones in both groups.Results　There were differences in tear secretion between A and B group (F=19.731,P=0.009).The tear secretion of group A was less than group B,which indicated the damage of the function of tear secretion.In addition,the differences of tear secretion in the two groups showed a increasing tendency with the prolongation of treatment.The tear secretion between the two groups was different on day 4 and 7 after dropping eyes,and the differences were statistically significant (t=3.847,5.695;P=0.026,0.009).Compare with group B,group A showed a shorter BUT (F=22.432,P=0.001),which indicated the damage of tear film function.The differences of the degree of tear film damage in the two groups showed a increasing tendency with the prolongation of treatment.The two groups showed difference in BUT on day 4 and 7 after dropping eyes,and the differences were statistically significant(t=5.753,5.695;P=0.024,0.009).Compare with group B,group A showed a deeper fluorescein stain of corneal epithelium（F=14.753,P=0.003）,which indicated the damage of corneal epithelial cell,and the differences of fluorescein stain of corneal epithelium in the two groups showed a increasing tendency with the prolongation of treatment.The two groups showed difference in FL on day 4 and 7 after dropping eyes,and the differences were statistically significant(t=7.537,9.864;P=0.031,0.012).Compare with group B,group A showed thinner corneal epithelium on day 7 after dropping eyes,and the differences were statistically significant (all P<0.05).Conclusion　Montmorillonite eye drops can damage the tear secretion function and the stability of tear film in mice as well as the corneal epithelial cells,leading to make corneal epithelium thinner.