ORIGINAL ARTICLES Effect of H-7 on Secondary Cataract After Phacoemulsification in the Live Rabbit Eye

Purpose: This study is aimed to determine if the serine-threonine kinase inhibitor H-7 inhibits secondary cataract after phacoemulsification in the live rabbit eye. Methods: Eighteen rabbits underwent extracapsular lens extraction by phacoemulsification in 1 eye. The eye was treated with intravitreal H-7 (300 or 1,200 mM; n 6 or 5) or balanced salt solution (BSS) (n 7) immediately after the surgery and twice weekly for 10 weeks. Each eye received slit lamp biomicroscopy once a week, during which posterior capsule opacification (PCO) was evaluated. The eye was then enucleated and the lens capsule was prepared, fixed, and imaged. PCO was evaluated again on the isolated lens capsule under a phase mi-croscope. Soemmering’s ring area (SRA) and the entire lens capsule area were measured from capsule images on a computer and the percentage of SRA (PSRA) in the entire capsule area was calculated. Wet weight of the capsule (WW) was determined on a balance. Results: No significant difference in PCO was observed in any comparison. No significant differences in SRA, PSRA, and WW were observed between the 300 mM H-7–treated eye and the BSS-treated eye. However, SRA, PSRA, and WW in the 1,200 mM H-7–treated eye were significantly smaller than those in the BSS-treated eye [28.3 16.2 vs. 61.4 8.86mm2 (P 0.001), 33% 20 % vs. 65% 15 % (P 0.01), and 65.6 27.9 vs. 127.0 37.3mg (P 0.01)]. Conclusions: Intravitreal H-7 (1,200 mM) significantly inhibits Soemmering’s ring formation in the live rabbit eye, suggesting that agents that inhibit the actomyosin system in cells may prevent secondary cataract after phacoemulsification