[Ocular penetration of UF-021, a new prostaglandin related compound, in the rabbit eye]

The ocular penetration and pigment affinity of topically applied UF-021, a newly developed prostaglandin-related compound, were investigated in rabbit eyes using 3H-labeled UF-021. Ten minutes to 24 hours after instillation of 0.12% of 3H-UF-021 solution into New Zealand white or pigmented rabbit eyes, the rabbits were sacrificed and the eyes were immediately enucleated. The extraocular muscles, conjunctiva, aqueous humor, cornea, iris, anterior and posterior sclera, ciliary body, lens, vitreous, retino-choroid complex, optic nerve were separated and blood samples were taken. The concentration of 3H-UF-021 in each sample was determined with a liquid scintillation counter. The peak concentration of UF-021 was obtained at 40 minutes and 1 hour after instillation in the iris-ciliary body and aqueous humor of albino rabbit. According to the pharmacokinetic analysis of the data, UF-021 showed good ocular penetration into the rabbit eye, and the permeability of the epithelial barrier for UF-021 was calculated to be 2.9 x 10(-3) cm/hr. The apparent elimination rate constant and the apparent absorption rate constant were also calculated to be 0.21 hr-1 and 1.28hr-1, respectively. The time course for 3H-UF-021 concentration in the eye of pigmented rabbit was almost the same as that in the eye of non-pigmented rabbit, indicating that UF-021 did not bind to pigmented tissues.