[Neuroprotective effect of N-methyl-D-aspartate receptor antagonists in an experimental glaucoma model in the rat].
OBJECTIVE
To evaluate the neuroprotective effect of memantine and dizocilpine, which are noncompetitive open-channel blockers of the N-methyl-D-aspartate (NMDA) receptor, on glaucomatous optic neuropathy in an experimental glaucoma model in the rat.


METHODS
Experimental glaucoma was induced in the right eyes of 30 Wistar albino rats by intracameral injection of India ink followed by laser trabecular photocoagulation 4 days later. The left eye served as a control. Either memantine, dizocilpine, or phosphate-buffered saline (PBS) was injected intraperitoneally just before trabecular photocoagulation. Five days later, 3% fast blue was injected into both superior colliculi. The eyes were enucleated another 3 days later and flat mounts of the retinas were prepared. Labeled ganglion cells were counted in the area 1 mm away from the optic disc.


RESULTS
Five days after laser application, no significant intraocular pressure (IOP) change in the right eye was found among the 3 groups. In eyes treated with memantine or dizocilpine, significantly more ganglion cells were labeled.


CONCLUSIONS
Systemically applied memantine and dizocilpine had a neuroprotective effect against experimental glaucomatous optic neuropathy in the rat.
Gu
Z
Z
Department of Ophthalmology, Gifu University School of Medicine, Japan.
Yamamoto
T
T
Kawase
C
C
Matsubara
M
M
Kawase
K
K
Sawada
A
A
Kitazawa
Y
Y
D000818:Animals; D004195:Disease Models, Animal; D016291:Dizocilpine Maleate / Q000627:therapeutic use*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D005901:Glaucoma / Q000188:drug therapy*; D008297:Male; D008559:Memantine / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*
D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate; D008559:Memantine