Age-related changes in the extracellular matrix of the human optic nerve head.

By using immunofluorescent staining we were able to characterize the age-related changes in the macromolecules making up the extracellular matrix of the lamina cribrosa of the human optic nerve head. As the cores of the cribriform plates enlarged with age, there were age-related increases in the apparent density of collagen types I and III and elastin that constituted the connective tissue support of the nerve bundles. Collagen type IV coated the cribriform plates as basement membranes and was also present within the cores as a fine filamentous network, which increased in density with age as the cribriform plates expanded. As this tissue ages, individual differences leading to more or less of a particular macromolecule of the extracellular matrix may alter the support function of the lamina cribrosa and influence the degeneration of the optic nerve associated with glaucoma.