Biochemical studies on the use of sodium hyaluronate in the anterior eye segment. III. Histological studies on distribution and efflux process of 5-aminofluorescein-labeled hyaluronate.

5-aminofluorescein-labeled hyaluronate was injected into the anterior chamber of rabbit eyes, and its distribution in the anterior segment and efflux process from the chamber were investigated. At an early stage after the injection, fluorescence was observed in the iris and corneo-scleral junction. The labeled hyaluronate in the lysosome separated from the iris had been degraded remarkably at this stage. These results suggest that the labeled hyaluronate injected into the chamber is eliminated not only through the aqueous plexus/sinus of the chamber angle but also through the iris and corneo-scleral junction by digestion with lysosomal hyaluronidase in the iris. On the other hand, fluorescence was observed at and after 12 hours in the corneal stroma. This finding means that a part of the labeled hyaluronate that had been distributed in the corneo-scleral junction permeated into the central part of the cornea through the extracellular space of the corneal stroma. Fluorescence could not be detected in the lens and ciliary body at any period after the injection.