肉毒杆菌B诱导大鼠干眼模型中泪腺Lacritin蛋白表达的研究

Expression of Lacritin protein in lacrimal gland of rat dry eye model induced by botulinum toxin B

目的建立肉毒杆菌B诱导大鼠干眼模型,通过观察泪腺Lacritin蛋白表达变化,初步探讨其在干眼症中的作用机理。方法 30只(30眼)健康8周雌性SD大鼠,随机分为2组,20只为实验组,10只为对照组。实验组右侧泪腺注射肉毒杆菌B 0.1 mL,对照组右侧泪腺注射生理盐水0.1 mL。分别于术前1 d及术后3 d、7 d、14 d、28 d、42 d观察基础泪液分泌量、角膜荧光染色。通过免疫组织化学染色和Western blot方法定性、定量分析Lacritin蛋白表达变化。结果实验组从术后3 d时出现泪液分泌减少,实验组为(2.56±0.72)mm,对照组为(3.04±0.72)mm,组间差异无统计学意义(P>0.05);实验组术后7 d、14d、28 d时分别为(2.03±0.86)mm、(2.01±0.78)mm、(1.04±0.46)mm,对照组分别为(3.01±0.42)mm、(2.78±0.54)mm、(3.00±0.21)mm,2组间差异均有统计学意义(均为P<0.05);在28 d实验组泪液分泌减少达到最低(1.04±0.46)mm;42 d后泪液分泌恢复,与对照组差异无统计学意义(P>0.05)。实验组角膜荧光染色3 d时出现,持续到42 d,除术前1 d和术后3d外,余时间点与对照组评分差异均有统计学意义(均为P<0.05)。实验组泪腺组织Lacritin蛋白含量检测显示:3 d开始减少,7 d达到最低,28 d时含量仍呈低表达,42 d开始恢复;对照组Lacritin蛋白含量各时间点未出现变化。结论泪腺注射肉毒杆菌B可以成功诱导大鼠炎症干眼模型,Lacritin蛋白的减少与眼表损坏有密切关系。

Objective Through establishing the botulinum toxin B-induced rat dry eye model, to explore the changes of lacritin protein expression in lacrimal gland and investigate its mechanism. Methods Thirty healthy female rats （30 eyes） with 8 weeks old were randomly divided into two groups,20 cases injected botulinum toxin B （0.1 mL） via lacrimal gland in right eyes （experimental group） ,and l0 cases injected saline （0. I mL, control group）. Schirmer I test and corneal fluorescein staining were performed at preoperative 1 day and postoperative 3 days,7 days,14 days,28 days and 42 days, and lacritin protein expression were observed by immunohistochemical staining and Western blot. Results The result of Schirmer I test in experimental group was significantly decreased from the postoperative 3 days （ 2.55 ± 0.72 ） ram, which in con trol group was （ 3. 04 ± 0. 72 ） nun, there was no statistical difference between two groups （P 〉 0.05 ） ; The results of Schirmer I test at postoperative 7 days, 14 days and 28 days in experimental group were （ 2.03 ± 0. 86） nun, （2.01± 0.78 ） nun and （ 1.04 ＋ 0. 45）mm, respectively, which in control group were （3. O1 ± 0.42 ）nun, （2.78 ± 0.54 ） nun and （3.00 ± 0.21 ）ram, respectively, there were statistical differences between two groups （ all P 〈 0.05 ） ; The result of Schirmer I test in experimental group reached the least peak at postoperative 28 days （ 1.04 ± 0.46） ram, and then returned to normal from 42 days, there was no statistical difference compared with control group （P 〉 0.05 ）. The positive corneal fluorescein staining appeared at postoperative 3 days in experimental group and maintained to 42 days, except for preoperative 1 day and postoperative 3days, there were statistical differences in staining scores at other time points between two groups （ all/~ 〈 O. O~ ）. Lacntm protein expression in lacrimal gland of experimental group decreased at postoperative 3 days, reached the least at 7 days and maintained to 28 days, then returned from 42 days, which in control group unchanged at different time points. Conclusion