The qualitative evaluation of the pharmacokinetics of subconjunctivally injected antifungal agents in rabbits.
Dutch-belted rabbits with corneal epithelium either intact or debrided were injected subconjunctivally with 300 microliters of one of six antifungal agents: 10 mg/ml miconazole, 5 mg/ml fluconazole, 5 mg/ml ketoconazole, 2.5 mg/ml itraconazole, and 5 mg/ml amphotericin B. At intervals of 10 min to 96 h after injection, animals were killed and corneas removed at the limbus. Three vertical strips from the right cornea and four contiguous 3-mm disks trephined from the central vertical axis of the left cornea were placed on agar plates seeded with an appropriate indicator organism. After 24 h of incubation, the zones of inhibition were measured. For itraconazole, miconazole, fluconazole, saperconazole, and ketoconazole, central corneal levels peaked by 2 h in normal and debrided corneas. Little or no drug was detectable after 4-8 h, except for itraconazole, which persisted in the cornea for at least 24 h in both normal and debrided corneas. Peak levels of amphotericin B in the central cornea were achieved after 2 h in rabbits with debrided corneas, with no drug activity measured after 8 h. There were no detectable levels of drug found in the central corneas of rabbits with intact corneal epithelium. On the basis of this pilot study, the method offers a rapid approach to the screening of antifungal agents for possible use by subconjunctival injection.
Klippenstein
K
K
Department of Ophthalmology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2540.
O'Day
D M
DM
Robinson
R D
RD
Williams
T E
TE
Head
W S
WS
D000818:Animals; D000935:Antifungal Agents / Q000493:pharmacokinetics*; D002175:Candida / Q000187:drug effects; D003228:Conjunctiva; D003315:Cornea / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D007267:Injections; D008826:Microbial Sensitivity Tests; D011817:Rabbits; D012441:Saccharomyces cerevisiae / Q000187:drug effects
D000935:Antifungal Agents