The Expression Of Occludin In Corneal Epithelium Atfer Flap-free Epi-LASIK And Lfap-free LASEK

Objective：To investigate and compare the expression of occludin in cornea epitheliumof a rabbit model after Flap-Free Epi-LASIK(Flap-free epipolis laser in-situkeratomihusi) and Flap-Free LASEK(Flap-Free laser-assisted subepithelial keratectom).Methods:24of48New Zealand rabbits were randomly treated with Flap-FreeEpi-LASIK and another24rabbits were treated with Flap-Free LASEK in the right eye,and other2rabbits were treated as blank controls. Treated eyes were randomly dividedinto four groups, and sacrificed at24,48,72,120hours after surgery. HE staining wasused to observed histological changes of corneal tissue. The expression of occludinprotein in the cornea epithelium was determined by immunofluorescence staining.RT-PCR was used to identify the level of mRNA in the central cornea.Result1. Histological ExaminationThe examination of morphological changes in the corneal epithelium showed thatthe epithelium stratifies to about2-3cell layers at48hours after surgery andepithelial cells recovering all wounds treated with either flap-free Epi-LASIK orflap-free LASEK at72hours post-wounding. And it was seen that there was nosignificant difference between the two groups during epithelial wound closure.2. ImunfluorescenceThe expression of occludin in the cornea epithelium of flap-free LASEK group wereweaker and disorganized than that in flap-free Epi-LASIK group at24h,48h and72h time point. At120h after surgery, the occludin staining in both flap-free LASEK andflap-free Epi-LASIK group are continuous and regular, and there is no significantdifference compared with control group.3. RT-PCRSemi-quantitative RT-PCR showed that the mRNA level of occludin in the centralcornea after flap-free LASEK were lower as compared with flap-free Epi-LASIKgroup from24to72hours(P<0.05), with no significant difference at120hours(P>0.05).Conclusion The reformation of occludin protein in flap-free Epi-LASIK group isfaster than that in flap-free LASEK group. Therefore, flap-free Epi-LASIK isadvantageous in reducing the stimulative symptoms and complication after the surgery.