title: Ocular application of nerve growth factor protects degenerating retinal ganglion cells in a rat model of glaucoma.
abstract: OBJECTIVE
  Elevated intraocular pressure is a crucial pathologic event for the development of glaucoma (GL). We have reported that nerve growth factor (NGF) reaches retinal cells and the optic nerve (ON) when applied to the eye. Whether ocular application of NGF prevents or reduces damage to retinal ganglion cell (RGC) is not known.
  
  
  METHODS
  GL was induced in adult rats by the injection of hypertonic saline into the episcleral vein of the right eye and the left eye used as control. Rats were then treated daily with ocular application of NGF or vehicle solution for 7 weeks. Retinal and ON tissues were then used for structural, immunohistochemical, and biochemical studies.
  
  
  RESULTS
  The injection of hypertonic saline into the episcleral vein led to progressive degeneration of RGCs, with the loss of nearly 40% of these cells after 7 weeks of treatment. This cellular loss is associated with the downregulation of NGF and NGF-receptor expression in the retina and ON of the glaucomatous eye and ocular treatment with NGF significantly reduced the deficit induced by GL.
  
  
  CONCLUSIONS
  These findings indicate that NGF can exert protective action on RGC degeneration occurring in glaucomatous retina. We suggest that ocular NGF treatment might be a suitable pharmacologic approach to investigate protective mechanisms of degenerating RGCs.
authors.affiliation: Department of Ophthalmology, IRCCS, G.B. Bietti Eye Foundation, Rome, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Colafrancesco
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Parisi
authors.forename: Valentina
authors.initials: V
authors.lastname: Sposato
authors.forename: Simona
authors.initials: S
authors.lastname: Rossi
authors.forename: Matteo Antonio
authors.initials: MA
authors.lastname: Russo
authors.forename: Marco
authors.initials: M
authors.lastname: Coassin
authors.forename: Alessandro
authors.initials: A
authors.lastname: Lambiase
authors.forename: Luigi
authors.initials: L
authors.lastname: Aloe
mesh_terms: D000287:Administration, Topical; D000818:Animals; D015153:Blotting, Western; D002452:Cell Count; D004195:Disease Models, Animal; D005901:Glaucoma / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D007150:Immunohistochemistry; D007429:Intraocular Pressure; D008297:Male; D009410:Nerve Degeneration; D020932:Nerve Growth Factor / Q000008:administration & dosage*; D009883:Ophthalmic Solutions / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D020800:Receptor, Nerve Growth Factor / Q000378:metabolism; D020917:Receptor, trkA / Q000378:metabolism; D012162:Retinal Degeneration / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D012165:Retinal Ganglion Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D014065:Tonometry, Ocular
chemical_list: D009883:Ophthalmic Solutions; D020800:Receptor, Nerve Growth Factor; D020932:Nerve Growth Factor; D020917:Receptor, trkA