NMDA receptor-independent epileptiform activity induced by magnesium-free solution in rat amygdala neurons is blocked by CNQX.
The effect of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), a specific non-N-methyl-D-aspartate (non-NMDA) receptor antagonist, on NMDA-independent epileptiform activity induced by Mg2(+)-free medium was studied in rat basolateral amygdala (BLA) neurons using intracellular recording techniques. Twenty to 30 min after switching to Mg2(+)-free medium, spontaneous and evoked epileptiform activity were observed in 16 out of 18 amygdala slices. Superfusion of D-2-amino-5-phosphonovalerate (D-APV), a selective NMDA receptor antagonist, reduced the duration of epileptiform activity by an average of 83%. However, there was a residual depolarizing component which remained in the presence of D-APV. This D-APV-resistant component could be completely blocked by CNQX suggesting that it is mediated by non-NMDA receptors.
Gean
P W
PW
Department of Pharmacology, College of Medicine, National Cheng-Kung University, Tainan City, Taiwan, Republic of China.
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology*; D000818:Animals; D003470:Culture Media; D004558:Electric Stimulation; D004827:Epilepsy / Q000209:etiology* / Q000503:physiopathology; D066298:In Vitro Techniques; D008275:Magnesium Deficiency / Q000150:complications*; D008297:Male; D009474:Neurons / Q000502:physiology*; D009994:Osmolar Concentration; D011810:Quinoxalines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology*
D003470:Culture Media; D011810:Quinoxalines; D016194:Receptors, N-Methyl-D-Aspartate; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D015763:2-Amino-5-phosphonovalerate