Movement of fluorescein and fluorescein glucuronide across the isolated rabbit iris-ciliary body.
Movement of fluorescein and fluorescein glucuronide, a fluorescent metabolite of fluorescein, across the isolated iris-ciliary body of the albino rabbit was determined under short-circuit conditions using a modified Ussing's chamber. The permeabilities of this tissue to these dyes were calculated. The outward permeability (from the aqueous to the stromal side) of the iris-ciliary body preparation averaged 6.63 +/- 0.86 for fluorescein and 1.51 +/- 0.47 X 10(-6) cm/sec for fluorescein glucuronide, and the inward permeability (from the stromal to the aqueous side) was 1.68 +/- 0.41 for fluorescein and 1.37 +/- 0.77 X 10(-6) cm/sec for fluorescein glucuronide, respectively. Application of probenecid or ouabain decreased the outward permeability of fluorescein, but it had no significant effect on the fluorescein glucuronide movement. Application of 10(-5) M 2,4-dinitrophenol showed no significant effect on the fluorescein or fluorescein glucuronide movement, but application of 5 X 10(-4) M 2,4-dinitrophenol decreased the outward fluorescein transfer, which was also markedly suppressed by incubation at 0 degrees C. It is possible that an active transport mechanism is involved in the outward fluorescein movement across the iris-ciliary body, while the inward movement of fluorescein and also the fluorescein glucuronide movement across this tissue is mainly by passive diffusion.
Eguchi
S
S
Department of Ophthalmology, University of Tokyo School of Medicine, Japan.
Araie
M
M
Takase
M
M
D019297:2,4-Dinitrophenol; D000818:Animals; D001692:Biological Transport; D002924:Ciliary Body / Q000378:metabolism* / Q000502:physiology; D004140:Dinitrophenols / Q000494:pharmacology; D004553:Electric Conductivity; D005260:Female; D019793:Fluorescein; D005452:Fluoresceins / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D010042:Ouabain / Q000494:pharmacology; D010539:Permeability; D011339:Probenecid / Q000494:pharmacology; D011817:Rabbits
D004140:Dinitrophenols; D005452:Fluoresceins; D010042:Ouabain; C041357:fluorescein glucuronide; D011339:Probenecid; D019297:2,4-Dinitrophenol; D019793:Fluorescein