Ultrastructural location of extracellular matrix components in the optic nerve head
J. C. Morrison, N. L. L'Hernault, J. A. Jerdan and H. A. Quigley
Glaucoma Service, Wilmer Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
The distributions of laminin and collagen types I through V were determined
in optic nerve heads of cynomolgus monkeys using colloidal gold
immunoelectron microscopy. Collagen types I and III localized to striated
collagen fibrils in arterial walls throughout the optic nerve head and to
fibrils comprising the core of the lamina cribrosa beams and optic nerve
septa. Collagen type IV and laminin localized to basement membranes of all
blood vessels and to basement membranes of astrocytes that lie between the
laminar beams and line the optic nerve septa and pia mater. Collagen type V
was detected both in striated collagen fibrils and in vascular and
astrocyte basement membranes. These results provide a detailed
understanding of the optic nerve head extracellular matrix distribution and
illustrate a sensitive method for future study of its role in glaucomatous
optic nerve damage.
