[Neuroprotection in ischemia of the retina in an animal model].
OBJECTIVE
The NMDA-receptorantagonist memantin is neuroprotective in retinal ischemia. Does this also apply to the NMDA-receptorantagonist cerestat and the glutamate release inhibitor riluzole?


METHODS
In 50 rats ischemia was induced by elevating the IOP of one eye to 120 mmHg for 1 h. The drugs were injected before ischemia because, according to our hypothesis, a neuroprotective effect would be most evident in prophylactic preischemia treatment. Ten rats received 20 mg/kg/d memantine s.c., 10 received 16.8 mg/kg/d cerestat s.c., 10 received 16 mg/kg/d riluzole i.p. and 20 rats served as controls. Two weeks later, the ischemic damage was histologically quantified by counting the number of neurons in the ganglion cell layer of retinal whole-mounts stained with cresyl violet.


RESULTS
In the memantine group 47% of the neurons survived ischemia, in the cerestat group 61%, and in the riluzole group 43%. In the control group the percentage was 28%. The differences from the control group were statistically significant (P < 0.05).


CONCLUSIONS
Cerestat, memantine and riluzole have a neuroprotective effect--reducing excitotoxic damage of retinal neurons. The relative drug potencies cannot be directly compared, because of differences in dosage and the route of administration.
Lagrèze
W A
WA
Universität-Augenklinik Freiburg.
Otto
T
T
Feuerstein
T J
TJ
D000818:Animals; D007429:Intraocular Pressure / Q000187:drug effects; D007511:Ischemia / Q000473:pathology*; D008297:Male; D008559:Memantine / Q000494:pharmacology*; D018696:Neuroprotective Agents / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D012160:Retina / Q000187:drug effects / Q000473:pathology; D012171:Retinal Vessels / Q000187:drug effects*
D018696:Neuroprotective Agents; D016194:Receptors, N-Methyl-D-Aspartate; D008559:Memantine
Neuroprotektion bei Ischämie der Netzhaut im Tiermodell.