SITE OF OCULAR HYDROLYSIS OF A PRODRUG, DIPIVEFRIN, AND A COMPARISON OF ITS OCULAR METABOLISM WITH THAT OF THE PARENT COMPOUND, EPINEPHRINE

  • 1 January 1980
    • journal article
    • research article
    • Vol. 19  (7) , 817-823
Abstract
Dipivefrin is a prodrug of epinephrine which is hydrolyzed to epinephrine after absorption into the eye. The major site of this hydrolysis is the cornea. Some dipivefrin is absorbed unchanged into ocular tissues, but most appears as epinephrine and its metabolites within 15 min after topical application. Metanephrine is the major metabolite of epinephrine in rabbit ocular tissues. It is found as soon as 15 min after application of dipivefrin or epinephrine and appears in all the tissues tested. The epinephrine which is liberated by hydrolysis of topically applied dipivefrin apparently is metabolized similarly to topically applied epinephrine. The monoamine oxidase metabolites of epinephrine appear 1-3 h after treatment and are found mainly in the aqueous humor. After ocular application of either compound uptake and storage of the exogenous epinephrine appears in the iris and ciliary body. Some storage of unmetabolized epinephrine exists in the cornea.