AIM: To investigate the effect of cyclosporine A(CsA)on the phosphatidylinositol-3 kinase(PI-3k)pathway during procession of proliferation in epithelial cells of rabbit lens, and provide treatment strategies for after cataract on the basis of experiment.

METHODS: Sixty eyes of 30 healthy white rabbits were operated by lens cortex removal in cataract surgery, and 30 right eyes were divided in treatment group and the other 30 eyes were divided in control group. From the first postoperative day, the control group eyes were dropped with normal saline 6 times each day, and the treatment group eyes were dropped with 1% CsA 6 times each day. Six rabbits were selected randomly and killed on the day before dropping and 1, 2wk, 1 and 2mo of postoperative day respectively. The lens of those killed rabbits were removed by surgery. The strategies of immunohistochemistry and mount in situ hybridization were used to detect the content of proliferating cell nuclear antigen(PCNA), gene of phosphate and tension homology deleted on chromsome ten(PTEN)mRNA, Ser473-R, respectively.

RESULTS: The expression of PCNA and Ser473-R were both down-regulate after operation in treatment group and control group, and the PCNA levels were significantly lower among treatment group than those in control group on 1wk(0.690±0.035 vs 0.785±0.015, t=6.099, P<0.01)and 2wk(0.571±0.038 vs 0.670±0.037, t=4.585, P<0.01). In addition, the levels of Ser473-R were significantly lower among treatment group than those in control group on 1wk(0.374±0.031 vs 0.435±0.030, t=3.486, P=0.006)and 2wk(0.220±0.022 vs 0.251±0.020, t=2.516, P=0.031). However, the expression levels of PTEN mRNA were continually increased 1wk～1mo after operation, in which the expression levels of PTEN mRNA were significantly higher among treatment group than those in control group on 1wk(0.302±0.027 vs 0.255±0.038, t=2.474, P=0.033).

CONCLUSION: 1% CsA could inhibit the proliferation of epithelial cells in lens of rabbits with after cataract through preventing PI-3k pathway.