[Effect of matrix metalloproteinase inhibitor on experimental pseudomonal corneal ulceration]

We examined the effect of matrix metalloproteinase (MMP) inhibitor (CS-610) on experimental pseudomonal corneal ulceration by clinical and histological evaluation. Intrastromal injection of 3.5 microliters sterile culture broth of P. aeruginosa, IID-1117 (13.5 unit Type I collagenase equivalent proteinase activities), was done to induce corneal ulcers in guinea pigs. The animals were divided into two groups of 23 each. The CS-610 group received topical CS-610 (400 micrograms/ml) treatment at 2-hour intervals and the control group received only the vehicle of CS-610 at the same intervals. In the control group, corneas developed acute corneal damage following corneal ulcerations at 6-12 hours. In the CS-610 group, these corneal lesions were inhibited in most of the eyes (p < 0.01). In the late period, as inflammatory cells migrated into the cornea, some animals of the CS-610 group developed corneal ulcer. The results indicated that CS-610 had a potent inhibitory activity against pseudomonal proteinases in vivo. The results also suggested that the mechanism of the ulceration model involved not only pseudomonal proteinases but also endogenous responses.