Blockade of retinal NMDA receptors by sodium nitroprusside is probably due to nitric oxide formation.
Effects of a nitric oxide (NO)-producing agent, sodium nitroprusside, on N-methyl-D-aspartate (NMDA) receptor activation in the cultured retinal neurons of rats were examined. NMDA in a Mg(2+)-free medium evoked inward currents at the resting membrane potential. Inward currents were also evoked by kainate. Sodium nitroprusside markedly reduced the NMDA-induced currents without affecting those induced by kainate. These results suggest the possible existence of a negative feed back system of NO which serves to regulate the activation of NMDA receptors in retinal neurons.
Ujihara
H
H
Department of Pharmacology, School of Medicine, Yamaguchi University, Ube, Japan.
Akaike
A
A
Tamura
Y
Y
Yokota
T
T
Sasa
M
M
Kashii
S
S
Honda
Y
Y
D000818:Animals; D005260:Female; D007608:Kainic Acid / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D009599:Nitroprusside / Q000494:pharmacology*; D011247:Pregnancy; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors* / Q000378:metabolism; D012160:Retina / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
D016194:Receptors, N-Methyl-D-Aspartate; D009599:Nitroprusside; D009569:Nitric Oxide; D016202:N-Methylaspartate; D007608:Kainic Acid