OX VITREOUS HUMOUR. 2. HYALURONIC ACID RELATIONSHIPS

Abstract

When ox vitreous humor is suspended in water, protein and hyaluronic acid diffuse out of the vitreous at different rates and are therefore independent of one another. No compound similar to a mucin has been found in the vitreous. The filtrate from a washed vitreous humor is not of uniform composition. This suggests the presence of an internal network in the vitreous impeding the movement of large particles, a theory which is substantiated by the fact that hyaluronidase, which disaggregates hyaluronic acid, acts much more slowly within the intact vitreous than within the vitreous filtrate. Thus the insoluble structural protein of the humor (collagen) helps to maintain the aggregated hyaluronic acid. Collagenase, which liquifies collagen, also disaggregates hyaluronic acid. This latter effect is due to the copper content of collagenase acting as a catalyst to the ascorbic acid of the vitreous, thus setting up a disaggregating system. When the copper is inhibited by the addition of Na diethyl dithiocarbamate the digestion of the collagen by collagenase is slowed down. Thus the presence of aggregated hyaluronic acid helps to maintain the structural protein.