The rewarding properties of NMDA and MK-801 (dizocilpine) as indexed by the conditioned place preference paradigm.
N-Methyl-D-aspartate (NMDA) ([R]-2-[Methylamino]succinic acid) is a specific excitatory amino acid. Two experiments were conducted to determine the rewarding properties of this compound using the conditioned place preference paradigm. In the first experiment, 40 male Sprague-Dawley rats received place preference conditioning for a 4 day period. The conditioned place preference apparatus consisted of two chambers with distinct visual and tactile cues, separated by a removable door. On days 2 and 4, rats were systemically administered NMDA (1.0, 15.0, and 30.0 mg/kg) paired with one chamber. On days 3 and 5, rats were systemically administered saline paired with the other chamber. Day 6 was the test day, and the rat was allowed free run of the entire apparatus in a drug-free state. Time spent in each side of the apparatus was computer recorded. NMDA produced a significant increase in the amount of time spent on the side previously paired with drug for 15.0 and 30.0, but not 1.0 mg/kg NMDA. In the second experiment, systemic administration of NMDA (30.0 mg/kg) paired with the noncompetitive NMDA receptor antagonist, MK-801 (0.5 mg/kg), resulted in neither place preference nor place aversion.
Panos
J J
JJ
Department of Psychology, The University of Wisconsin-Milwaukee, 53211, USA.
Rademacher
D J
DJ
Renner
S L
SL
Steinpreis
R E
RE
D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects*; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012201:Reward; D012646:Self Administration
D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate