EVALUATION OF INTRAOCULAR PENETRATION OF TOPICALLY ADMINISTERED TISSUE-PLASMINOGEN ACTIVATOR IN DOGS

Topically administered tissue plasminogen activator (tPA) was evaluate d for its penetration into aqueous humor of clinically normal dogs. Tw o concentrations of tPA (5 mg/ml and 10 mg/ml) were evaluated in a sin gle-dose study, and a concentration of 5 mg of tPA/ml was used for a m ultiple-dose study. The contralateral eye served as a nontreated contr ol. Enzyme substrate analysis of aqueous humor was used to determine t PA activity, The activity of tPA in aqueous humor was significantly (P less-than-or-equal-to 0.05) greater in treated eyes of all dogs, comp ared with that in control eyes. Significant differences in activity of tPA were not detected at different doses in treated eyes.