NMD A receptors antagonist

There have been a number of observations which show increased excitation and/or reduced inhibition in slices prepared from human epileptic brain tissue. Thus burst discharges can be evoked with stimuli that would not do so in normal animal tissue and these can be blocked by NMD A receptor antagonists. The inhibitory postsynaptic currents (IPSCs) in hippocampal dentate granule cells in slices prepared from temporal lobe epileptic tissue are in fact reduced by stimulation that activates NMDA currents (Isokawa 1996), which are more prolonged than usual and show changes in slope conductance. 

Dubray, C., Alloui, A., Bardin, L., Rock, E., Mazur, A., Rayssiguier, Y., Eschalier, A., Lavarenne, J. Magnesium deficiency induces an hyperalgesia reversed by the NMD A receptor antagonist MK801, Neuroreport 1997, 8, 1383-1386. 

Rabben T. Effects of the NMD A receptor antagonist ketamine in electrically induced A delta-fiber pain. Methods Find Exp Clin Pharmacol 2000 22(3) 185-9. 

Sadikot AF, Burhan AM, Belanger MC, Sasseville R (1998) NMD A receptor antagonists influence eai ly development of GABAergic intemeui ons in die mammalian stiiatum. Brain Res Dev Brain Res 105 35 2. 

Trullas R, Skolnick P (1990) Functional antagonists at the NMD A receptor complex exhibit antidepressant actions. Fur J Pharmacol 185 1-10. 

Dextromethorphan is the dextrorotatory isomer of the synthetic opioid levorphanol and is thought to act as a central nervous system antitussive (1). It binds to CNS sigma opioid binding sites and increases 5-HT concentrations by inhibiting uptake and by enhancing the release of 5-HT. It is also an antagonist at NMD A receptors. 

Papa SM, Engber TM, Boldry RC et al (1993) Opposite effects of NMD A and AMPA receptor blockade on catalepsy induced by dopamine receptor antagonists. Eur J Pharmacol 232 247-253... 

Ibogaine appears to be an antagonist with this receptor [305, 306] and, in an indirect way, repeated administration of morphine causes increased expression of a glutamate receptor subunit [307]. There are also probably some glutamate receptors for which NMD A is not an agonist [304]. 

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