CGRP increases the rate of corneal re-epithelialization in an in vitro whole mount preparation

A number of studies have localized CORP to nerves in the cornea and iris, and it is thought that CORP, along with other neuropeptides, is involved in pain sensation. It is also possible that CORP could mediate trophic influences between nerve endings and corneal epithelium. This investigation utilized an in vitro rabbit corneal whole mount preparation to study the effect of topical 2.5 mu M CORP application on epithelial wound healing rates of 5 mm diameter epithelial wounds. CGRP(2.5 mu M) was applied topically to 5 mm epithelial wounds at 0, 4, 16, 20, 24, 28, 40, 44, 48, 52, 56, 64, 68, and 72 hours after wounding and healing was visualized with fluorescein. CORP was found to increase the epithelial wound healing rate by 25%, from 51 +/- 3 mu m/hr for the control corneas, to 64 +/- 2 mu m/hr for CORP-treated corneas (mean +/- standard error, n = 10). Histological examination of the corneas following healing showed that the epithelium of the CORP-treated corneas healed in a similar manner as in the control corneas. These findings may have clinical utility for the understanding and treatment of corneal and other epithelial wounds.