[Changes in extracellular matrix components after excimer laser photoablation in rat cornea]

To understand the response of rat corneal wound healing after excimer laser photoablation, we observed the chronological changes in the localization of type I collagen, fibronectin, laminin, and type IV collagen after photoablation of the rat cornea. With immunofluoresence techniques, no obvious changes in the localization of type I collagen could be observed in the area of the wound. However, the localization of fibronectin, laminin, and type IV collagen was dramatically changed. One day after ablation, the fluorescein intensity of fibronectin increased at the denuded surface. After that, fibronectin, laminin, and type IV collagen were dramatically increased, especially in the shallow layer of the stroma, until about 7 days after ablation. In hematoxylin-eosin staining, keratocytes disappeared transiently from the area of the wound 1 day after ablation and then activated keratocytes migrated to the area. These results suggested that activated keratocytes might actively synthesize the extracellular matrix components. Therefore, sustained responses of keratocytes may be induced by excimer laser photoablation.