Effects of synthetic inhibitor of metalloproteinase and cyclosporin A on corneal haze after excimer laser photorefractive keratectomy in rabbits.
To evaluate the effects of synthetic inhibitor of metalloproteinase (SIMP) and cyclosporin A (CsA) on corneal haze after excimer laser photorefractive keratectomy (PRK) in rabbits, PRK was performed on 60 rabbits. They were randomized to one of four groups: group A which received topical SIMP, group B which received topical CsA, group C which received both SIMP and CsA, and group D which received vehicles. Another 16 rabbits did not undergo PRK and were randomized to one of four groups: group E which received topical SIMP, group F which received topical CsA, group G which received both SIMP and CsA, and group H which received vehicles. SIMP solution (1 mm) was instilled every two hours and 2% cyclosporin was instilled four times a day, this was carried out for as long as 6 weeks after surgery. At one, two, four, and six weeks after surgery, slit lamp examination was performed with haze gradings recorded, and corneal specimens were obtained from groups A, B, C, and D. In groups E-H, all rabbits were killed after six weeks of eyedrops instillation. Light microscopy and immunohistochemistry for collagen types III, IV, and VI were performed on the specimens obtained. Slit lamp examination and light microscopy revealed that SIMP significantly reduced corneal haze after PRK, but CsA did not. Immunohistochemistry revealed that deposition of types III and IV collagen was detected in ablated area in groups A-D, and SIMP reduced the frequency of positive staining for type III collagen. In groups E-F, corneas were normal. These findings suggest that SIMP significantly reduced corneal haze and the synthesis of type III collagen after excimer laser PRK in rabbits.
Chang
J H
JH
Department of Ophthalmology, Seoul City Boramae Hospital, Seoul, Korea.
Kook
M C
MC
Lee
J H
JH
Chung
H
H
Wee
W R
WR
D000818:Animals; D003094:Collagen / Q000378:metabolism; D003315:Cornea / Q000187:drug effects* / Q000378:metabolism / Q000601:surgery; D016572:Cyclosporine / Q000494:pharmacology*; D004151:Dipeptides / Q000494:pharmacology*; D007150:Immunohistochemistry; D053685:Laser Therapy; D054018:Lasers, Excimer; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors; D018903:Photorefractive Keratectomy / Q000379:methods*; D011480:Protease Inhibitors / Q000494:pharmacology*; D011817:Rabbits; D014945:Wound Healing / Q000187:drug effects
D004151:Dipeptides; C075190:HSCH2CH(CH2CH(CH3)2)CO-Phe-Ala-NH2; D011480:Protease Inhibitors; D016572:Cyclosporine; D003094:Collagen; D008666:Metalloendopeptidases