Effects of intraocular pressure change on movement of FITC-dextran across vitreous-aqueous interface.
In an attempt to study the effect of change in the intraocular pressure (IOP) on the status of the vitreous-aqueous interface, the effect of topical bunazosin was studied in the rabbit eye using the new Johnson-Maurice method. This entails an intravitreal injection of FITC-dextran and measurements of its concentration changes in the anterior chamber many days after the injection. Repeated instillations of bunazosin solution reduced the IOP by about 5 mmHg, without changing the aqueous flow rate as determined by the method of fluorometry. On the other hand, the FITC-dextran concentration in the anterior chamber increased, indicating that the movement of FITC-dextran from the vitreous into the aqueous was greater when the IOP was lowered. This increase in the FITC-dextran movement into the anterior chamber was thought to be mainly attributable to an increase in the anteriorly directed fluid movement across the vitreous-aqueous interface. The increase in the fluid movement was estimated to be about 1.3 microliter/hour. This study suggested that a reduction in the IOP generated a small fluid flow from the vitreous into the aqueous, and that the new Johnson-Maurice method can be a useful means for noninvasive investigations of the physiology of the vitreous-aqueous interface.
Sugiura
Y
Y
Department of Ophthalmology, University of Tokyo School of Medicine.
Araie
M
M
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D000867:Anterior Chamber / Q000378:metabolism; D001082:Aqueous Humor / Q000378:metabolism*; D003911:Dextrans / Q000493:pharmacokinetics; D005260:Female; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives*; D005452:Fluoresceins / Q000493:pharmacokinetics; D005470:Fluorometry; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D011799:Quinazolines / Q000494:pharmacology; D011817:Rabbits; D014822:Vitreous Body / Q000378:metabolism*
D000317:Adrenergic alpha-Antagonists; D003911:Dextrans; D005452:Fluoresceins; D011799:Quinazolines; C015219:fluorescein isothiocyanate dextran; C018176:bunazosin; D016650:Fluorescein-5-isothiocyanate