The Change of Interleukin-1beta & Nitric Oxide in Tear after Excimer Laser Photorefractive Keratectomy

ABSTRACT

This study was performed to investigate the amount of IL-1beta & NO in tear film after Excimer laser PRK and to determine whether NO induces cytotoxicity associated with apoptosis of keratocytes. Twelve myopes underwent PRK and were divided into 3 groups according to spherical equivalent. IL-1beta and NO production were measured at preop and postop 1, 4, 7 days, and expression of NOS and apoptosis of keratocytes were evaluated in the corneas of rats at 2 days after PRK. IL-1beta and NO production were significantly increased at postop 1 day(p<0.01) and then gradually decreased to preop levels at postop 7 days. The corneas of rats at 2 days after PTK revealed increased expression of NOS(iNOS, bNOS) and increased apoptosis of keratocytes in stroma of cornea. The degree of corneal opacity and NO production at postop 1 days were increased, positively correlated to ablation depth. It is suggested that NO production induced by IL-1beta may be related with apoptosis of keratocyte, which can influence on the corneal opacity after PRK.