无防腐剂的1％利多卡因对兔晶状体上皮细胞影响的组织病理学研究

Histopathological study of the effect of preservative-free 1% lidocaine on rabbit lens epithelial cells

目的探讨无防腐剂的1％利多卡因对兔晶状体上皮细胞（LECs）的影响，为寻求白内障术中清除上皮，预防囊膜混浊的有效药物提供实验依据。方法采集29只兔（58只眼）晶状体前囊膜及赤道部囊膜标本，分为3组，对照组囊膜不加药物处理、BSS组囊膜用BSS浸泡1min、利多卡因组囊膜用利多卡因浸泡1min，后行锥虫蓝-茜素红染色，显微镜照相，观察LECs活性同时对死亡细胞进行计数；并通过HE染色及透射电镜观察兔LECs的组织病理学改变。锥虫蓝．茜素红染色及死亡细胞计数15只兔（30只眼）：其中对照组5只兔（10只眼），BSS组5只兔（10只眼），利多卡因组5只兔（10只眼）；HE染色9只兔（18只眼）：其中对照组1只兔（2只眼），BSS组4只兔（8只眼），利多卡因组4只兔（8只眼）；透射电镜5只兔（10只眼）：其中对照组1只兔（2只眼），BSS组2只兔（4只眼），利多卡因组2只兔（4只眼）。结果对照组兔晶状体前囊膜上皮细胞死亡率（1．51±0．39）％，赤道部囊膜上皮细胞死亡率（1．52±0．32）％；BSS组兔晶状体前囊膜上皮细胞死亡率（1．78±0．50）％，赤道部囊膜上皮细胞死亡率（1．77±0．47）％；利多卡因组兔晶状体前囊膜上皮细胞死亡率（13．01±4．67）％，赤道部囊膜上皮细胞死亡率（9．59±3．35）％。经嵌套试验的方差分析，利多卡因组细胞死亡率明显高于对照组与BSS组（P〈0．05）。HE染色显示对照组与BSS组兔LECs仍贴附于囊膜上，未见明显病理改变。利多卡因组部分细胞与囊膜间产生空隙，并从囊膜上脱落，细胞空泡变性。透射电镜观察下对照组与BSS组细胞间及细胞与囊膜间连接完整。利多卡因组部分细胞间及细胞与囊膜间的连接被破坏，细胞脱落较多，排列松散。细胞膜塌陷，胞质内有大量的空泡形成，细胞结构被破坏。结论无防腐剂的1％利多卡因能松解兔LECs间及细胞与晶状体囊膜间的连接，并可导致LECs变性、死亡。

Objective To assess whether preservative-free 1% lidocaine is capable of loosing the junction between the rabbit lens epithelial cells （LECs） and between the cells and capsules and is capable of destroying the LECs, in order to provide scientific basis for pursuing safe and effective drugs to eliminate LECs in cataract surgery and to prevent capsular pacification, Methods Lens capsule specimens were collected from 29 rabbits （58 eyes） and divided into 3 groups ： balanced salt solution （BSS） group （ exposed to BSS for 1 minute）, lidocaine group （ exposed to preservative-free 1% lidocaine for 1 minute） and the control group. Specimens were stained with trypan blue and alizarin red, Photomicrographs of each capsule were taken to observe the viability of LECs and count the number of dead LECs, The histopathologic changes of LECs treated with lidocaine were evaluated by histological method and transmission electron microscope, Results The rate of dead LECs of the anterior and the equatorial lens capsules in control group was（ 1.51 ± 0. 39） %, and （ 1. 52 ± 0. 32） %, respectively, The rate of dead LECs of the anterior and the equatorial lens capsules irrigated with BSS was （ 1. 78 ± 0.50） % and （ 1.77 ± 0.47 ） %. The rate of dead LECs of the anterior and the equatorial lens capsules irrigated with preservative-free 1% lidocaine was（ 13. 01 ± 4. 67 ）% and（9.59±3. 35）%, respectively, The nested design ANOVA showed that the rate of dead LECs in the lidocaine group was greater than that in the control group or BSS group （ P 〈 0.05 ）, There was no significant difference in the number of dead cells between the anterior lens capsules and the equatorial lens capsules. After irrigated with lidocaine, cavities appeared ibetween the LECs and the capsule, cells detached from the capsule and showed vacuoles. The capsules of control group and BSS group showed a normal layer of LECs attached to the capsule. Under transmission electron microscope, in the lidocaine group, the junction between LECs and between the cell and the capsule were destroyed, many cells detached from the capsule and the rest arranged loosely. Some LECs dented, and many vacuoles emerged, resulting in destruction of the cellular frame. Conclusion Preservative-free 1% lidocaine may loose the junction between the LECs and between the cells and capsules, resulting in degeneration and death of the LECs.