Differential effects of the excitatory amino acid antagonists, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and 3-((+-)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP), on spinal reflex activity in mice.
Intrathecal administration of the preferential quisqualate antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) in anesthetized mice depressed Hoffmann (H)-reflexes, while flexor reflexes remained unaffected. The depressant effect of CNQX on H-reflexes was dose-dependent (range 0.1-10 nmol). The intrathecal administration of the selective N-methyl-d-aspartate (NMDA) antagonist 3-[(+-)-2-carboxypiperazin-4-yl]-propyl-1-phosphonate (CPP) reduced flexor reflexes (range 10-100 nmol) and had no effect on H-reflexes. These results suggest that H-reflexes in mice are mediated by spinal non-NMDA receptors, while flexor reflexes involve NMDA receptors.
Turski
L
L
Research Laboratories of Schering AG, Berlin, F.R.G.
Bressler
K
K
Klockgether
T
T
Stephens
D N
DN
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D000818:Animals; D006181:H-Reflex / Q000187:drug effects*; D008297:Male; D051379:Mice; D010879:Piperazines / Q000494:pharmacology*; D011810:Quinoxalines / Q000494:pharmacology*; D017459:Receptors, Amino Acid; D011956:Receptors, Cell Surface / Q000037:antagonists & inhibitors / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000502:physiology; D012023:Reflex, Monosynaptic / Q000187:drug effects*; D013116:Spinal Cord / Q000187:drug effects / Q000502:physiology*
D010879:Piperazines; D011810:Quinoxalines; D017459:Receptors, Amino Acid; D011956:Receptors, Cell Surface; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; C050592:3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid