Biochemical studies on the use of sodium hyaluronate in the anterior eye segment. II. The molecular behavior of sodium hyaluronate injected into anterior chamber of rabbits.

The behavior of sodium hyaluronate injected into the anterior chamber of rabbits was investigated using a 1% (w/v) solution of sodium hyaluronate having a molecular weight of 800K. Although the aqueous humor contained a considerable amount of reduced ascorbic acid, the molecular weight of sodium hyaluronate injected into the anterior chamber did not change. This was due to existence of a protecting factor for degradation of sodium hyaluronate in a low molecular weight fraction of the aqueous humor. The injected sodium hyaluronate was found to aggregate with proteins in the aqueous humor within 2 hrs. However, this aggregation did not affect the degradation of sodium hyaluronate with ascorbic acid. The hyaluronic acid content in the iris-ciliary body increased about three times as much as the normal level 2 hrs after the sodium hyaluronate injection. This result suggests that the injected sodium hyaluronate is not only eliminated through the angular aqueous plexus but also through the iris-ciliary body, followed by digestion with hyaluronidase in those tissues.