CEFYBO   02669
CENTRO DE ESTUDIOS FARMACOLOGICOS Y BOTANICOS
Unidad Ejecutora - UE
artículos
Título:
Therapeutic benefit of radial optic neurotomy in a rat model of glaucoma.
Autor/es:
BELFORTE NA; SANDE PH; DE ZAVALÍA N; DORFMAN D; ROSENSTEIN RE
Revista:
PLOS ONE
Editorial:
PUBLIC LIBRARY SCIENCE
Referencias:
Lugar: San Francisco; Año: 2012 vol. 7 p. 34574 - 34582
ISSN:
1932-6203
Resumen:
Radial optic
neurotomy (RON) has been proposed as a surgical treatment to alleviate the
neurovascular compression and to improve the venous outflow in patients with
central retinal vein occlusion. Glaucoma is characterized by specific visual
field defects due to the loss of retinal ganglion cells and damage to the optic
nerve head (ONH). One of the clinical hallmarks of glaucomatous neuropathy is
the excavation of the ONH. The aim of this work was to analyze the effect of
RON in an experimental model of glaucoma in rats induced by intracameral
injections of chondroitin sulfate (CS). For this purpose, Wistar rats were
bilaterally injected with vehicle or CS in the eye anterior chamber, once a
week, for 10 weeks. At 3 or 6 weeks of a treatment with vehicle or CS, RON was
performed by a single incision in the edge of the neuro-retinal ring at the
nasal hemisphere of the optic disk in one eye, while the contralateral eye was
submitted to a sham procedure. Electroretinograms (ERGs) were registered under
scotopic conditions and visual evoked potentials (VEPs) were registered with
skull-implanted electrodes. Retinal and optic nerve morphology was examined by
optical microscopy. RON did not affect the ocular hypertension induced by CS.
In eyes injected with CS, a significant decrease of retinal (ERG a- and b-wave
amplitude) and visual pathway (VEP N2-P2 component amplitude) function was
observed, whereas RON reduced these functional alterations in hypertensive
eyes. Moreover, a significant loss of cells in the ganglion cell layer, and
Thy-1-, NeuN- and Brn3a- positive cells was observed in eyes injected with CS,
whereas RON significantly preserved these parameters. In addition, RON
preserved the optic nerve structure in eyes with chronic ocular hypertension.
These results indicate that RON reduces functional and histological alterations
induced by experimental chronic ocular hypertension.