ENDOTHELIN-1 PROMOTES CORNEAL EPITHELIAL WOUND-HEALING IN RABBITS

This study is an attempt to determine the effect of endothelin-1 (ET-1 )-containing eyedrops on the rate of corneal epithelial wound closure in rabbits. After corneal epithelial debridement of about 50-60 mm(2) with n-heptanol, eyedrops containing either 10(-8) M ET-1 or 10(-6) M ET-1 were applied at five different times for the next three days. The wound was serially photographed 12, 24, 36, 48, 60 and 72 hours later to measure the extent of healing with a computerized planimeter. The respective wound healing rate at 10(-6) and 10(-8) M ET-1 was 1.293 +/ - 0.040 mm(2)/hour (n = 11) and 1.262 +/- 0.087 mm(2)/hour (n = 6), re spectively. These rates were 29% (P < 0.01) and 26% (p < 0.05) above t he control value, 1.005 +/- 0.063 mm(2)/hour (n = 13). Reepithelializa tion was not associated with any epithelial hyperplasia, neovasculariz ation or conjunctival hyperemia. These results suggest that ET-1-conta ining eyedrops could be of therapeutic value in the remedy of corneal epithelial defects.