title: Susceptibility to N-methyl-D-aspartate toxicity in morphological and functional types of cat retinal ganglion cells.
abstract: BACKGROUND
  To examine whether different types of retinal ganglion cells (RGCs) in the cat retina have different survival rates when exposed to N-methyl-D-aspartate (NMDA).
  
  
  METHODS
  NMDA injury was induced by intravitreal administration of NMDA at final concentrations of 0.2, 0.4, 0.6, and 0.8 mM. The total number of surviving RGCs and their distribution were counted by retrograde labeling with a fluorescent dye. Measurements of the proportions of the main RGC types (alpha, beta, and neither alpha nor beta cells) were obtained by using intracellular injections of Lucifer yellow.
  
  
  RESULTS
  The mean percentage of surviving RGCs in the NMDA-injected retina was reduced to 59.4% (0.2 mM NMDA), 35.8% (0.4 mM), 10.8% (0.6 mM), and 14.1% (0.8 mM). At 0.2 mM, the survival rate of alpha cells was reduced to 56%, but that of beta cells remained at 81%. At 0.8 mM, the survival rate of alpha cells was 19%, while beta cells rapidly decreased to 9.9%. No difference was detected in NMDA vulnerability between ON- and OFF-center RGCs.
  
  
  CONCLUSIONS
  Different RGC types display different susceptibilities to NMDA injury. A specific examination of the functions of different types of RGCs would be helpful in detecting retinal excitotoxicity such as in chronic retinal ischemia.
authors.affiliation: Department of Ophthalmology, Tohoku University Graduate School of Medicine, Aoba-ku, Sendai, Japan. ntoru@oph.med.tohoku.ac.jp
authors.forename: Toru
authors.initials: T
authors.lastname: Nakazawa
authors.forename: Masami
authors.initials: M
authors.lastname: Watanabe
authors.forename: Hideyo
authors.initials: H
authors.lastname: Kudo
authors.forename: Kohji
authors.initials: K
authors.lastname: Nishida
authors.forename: Makoto
authors.initials: M
authors.lastname: Tamai
mesh_terms: D000818:Animals; D002415:Cats; D002452:Cell Count; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D018690:Excitatory Amino Acid Agonists / Q000633:toxicity*; D007267:Injections; D007546:Isoquinolines / Q000008:administration & dosage; D016202:N-Methylaspartate / Q000633:toxicity*; D010641:Phenotype; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000187:drug effects*; D014822:Vitreous Body
chemical_list: D018690:Excitatory Amino Acid Agonists; D007546:Isoquinolines; D016202:N-Methylaspartate; C017475:lucifer yellow
references.citation: Prog Retin Eye Res. 2002 Nov;21(6):529-53
references.pmid: 12433376
references.citation: J Neurosci. 1999 Apr 1;19(7):2568-79
references.pmid: 10087070
references.citation: Mol Vis. 2005 Dec 27;11:1173-82
references.pmid: 16402025
references.citation: Neuroscience. 2003;116(3):733-42
references.pmid: 12573715
references.citation: J Neurophysiol. 1984 Dec;52(6):999-1013
references.pmid: 6520634
references.citation: J Neurosci. 1993 May;13(5):2105-17
references.pmid: 8478691
references.citation: J Neurobiol. 1995 Jun;27(2):189-203
references.pmid: 7658200
references.citation: Neuroscience. 2006 Jun 30;140(2):517-28
references.pmid: 16549267
references.citation: Invest Ophthalmol Vis Sci. 1999 Mar;40(3):713-20
references.pmid: 10067975
references.citation: Neuroscience. 2007 Aug 10;148(1):53-64
references.pmid: 17629411
references.citation: Graefes Arch Clin Exp Ophthalmol. 2006 Aug;244(8):1003-9
references.pmid: 16411104
references.citation: Vis Neurosci. 2001 Jan-Feb;18(1):137-45
references.pmid: 11347811
references.citation: Yan Ke Xue Bao. 2000 Sep;16(3):199-202
references.pmid: 12579648
references.citation: J Ocul Pharmacol Ther. 1997 Apr;13(2):129-37
references.pmid: 9090613
references.citation: Curr Eye Res. 2003 Jan;26(1):55-63
references.pmid: 12789537
references.citation: Surv Ophthalmol. 1999 Jun;43 Suppl 1:S102-28
references.pmid: 10416754
references.citation: Arch Ophthalmol. 1997 Sep;115(9):1161-6
references.pmid: 9298058
references.citation: Annu Rev Neurosci. 1979;2:193-225
references.pmid: 120128
references.citation: Invest Ophthalmol Vis Sci. 1999 Sep;40(10):2391-7
references.pmid: 10476807
references.citation: Ophthalmologica. 2005 Nov-Dec;219(6):379-85
references.pmid: 16286799
references.citation: J Neurochem. 2007 Feb;100(4):1018-31
references.pmid: 17266736
references.citation: Invest Ophthalmol Vis Sci. 2001 Apr;42(5):1096-106
references.pmid: 11274091
references.citation: Invest Ophthalmol Vis Sci. 2004 Dec;45(12):4352-8
references.pmid: 15557443