Components of vitreous-soluble proteins: effect of hyperoxia and age.

In young puppies, the retina, which is incompletely vascularized at birth becomes fully vascularized at approximately four weeks of age. During this period of vessel growth the total content of vitreous-soluble protein was found closely associated with the rate of retinal vessel growth. As vascularization progressed toward completion, the protein originally present at birth decreased to a negligible or undetected amount. Intravitreal neovascularization was produced in young puppies by exposure to 85 per cent oxygen for four days, then removal to room air. This form of neovascularization resembles closely that observed in human proliferative diabetic retinopathy. The oxygen treatment, which initially produced retinal capillary closure, then neovascularization, was associated with a retention of vitreous-soluble protein at a high level for several days. The results raise the possibility that the vitreous protein(s) may be fundamentally involved in the process of normal vascularization of the retina and in retinal neovascularization.