Abstract: To investigate the apoptosis cell in posterior sclera and to evaluate the apoptotic and the proliferative changes in lensinducted myopia. Method： A -20 D concave or -10 D concave was worn over the right eye in 30 fourweekold pigmented guinea pigs. The eyes were examined periodically with retinoscopy, and ascan ultrasonography. Two weeks later, the eyeballs were removed and the apoptosis cells were determined by electron microscopy, TUNEL technique and flow cytometry in sclera. Result: All eyes treated with -10.00 D or -20.00 D concave lens developed defocusinduced myopia. And axial lengths in lensinduced eyes remarkably increased in comparison with its control eyes. Apoptosis cells were observed in fibroblasts of sclera in the lensinduced eyes. Both the value of apoptotic index and the apoptosis rate in lensinduced eyes were significantly higher than the control group(P＜0.01), and the value of proliferative index was lower than the control group(P＜0.01). Conclusion： With the decreasing of the proliferation, the apoptosis cell increases in the posterior scleral fibroblasts in lensinduced myopia eye.

Key words: Myopia, Sclera, Apoptosis, Guinea pigs