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Abstract #20483 Published in IGR 10-1
Axons of retinal ganglion cells are insulted in the optic nerve early in DBA/2J glaucoma
Howell GR; Libby RT; Jakobs TC; Smith RS; Phalan FC; Barter JW; Barbay JM; Marchant JK; Mahesh N; Porciatti VThe Journal of Cell Biology 2007; 179: 1523-1537
See also comment(s) by John Danias •
Here, we use a mouse model (DBA/2J) to readdress the location of insult(s) to retinal ganglion cells (RGCs) in glaucoma. We localize an early sign of axon damage to an astrocyte-rich region of the optic nerve just posterior to the retina, analogous to the lamina cribrosa. In this region, a network of astrocytes associates intimately with RGC axons. Using BAX-deficient DBA/2J mice, which retain all of their RGCs, we provide experimental evidence for an insult within or very close to the lamina in the optic nerve. We show that proximal axon segments attached to their cell bodies survive to the proximity of the lamina. In contrast, axon segments in the lamina and behind the eye degenerate. Finally, the Wld(s) allele, which is known to protect against insults to axons, strongly protects against DBA/2J glaucoma and preserves RGC activity as measured by pattern electroretinography. These experiments provide strong evidence for a local insult to axons in the optic nerve.
Dr. S.W.M. John, Jackson Laboratory, Bar Harbor, ME 04609, USA. Simon.john@jax.org
Classification:
5.1 Rodent (Part of: 5 Experimental glaucoma; animal models)
2.13 Retina and retinal nerve fibre layer (Part of: 2 Anatomical structures in glaucoma)
