[Neovascularization in rat optic nerve]

The study aims at assessing possible age-induced alterations in the nervous vascular network by examining the microcirculation of the optic nerve in rats grouped by age. Histological specimens were stained with hematoxiline-eosine, the Romhany-Barzu dye staining and the Gomory tri-chromic dye staining. The volume, section surface and total surface of 2-6 micro and 7-14 micro vessels were determined on a total of 960 vessels of this group, over a five square millimeter area. The tables show the increase of vascular parameters from birth to adulthood, and the fact that not all the vessels were injected in old animals. The density of the vessels per square millimeter, their average length and average diameters, error calculus, variation coefficient, Student test and chi2 allow assessing the differences between animals belonging to the same species but to different age groups, or under the influence of medication.