Comparative anterograde amnestic and anticonvulsant effects of two types of NMDA receptor antagonists: MK-801 and HA-966.
The anterograde amnestic effects of non-competitive NMDA antagonists MK-801 and HA-966 on classic fear conditioning in goldfish (Carassius auratus) were examined in a series of experiments. Experiments 1 and 2 contrasted the anterograde amnestic effects of MK-801, (+)HA-966, and (-)HA-966. Experiment 3 examined the effects of MK-801 and (+)HA-966 on the expression of conditioned responses. Experiments 4 and 5 investigated whether the potency of MK-801, (+)HA-966 or (-)HA-966 in blocking NMDA-induced convulsions paralleled their potency in producing amnesia. The results showed that MK-801 was more potent than (+)HA-966 in producing anterograde amnesia and impairing expression, while (-)HA-966 did not produce anterograde amnesia. The anticonvulsant potency of MK-801, (+)HA-966, and (-)HA-966 paralleled their amnestic potency. These findings suggested that MK-801 and (+)HA-966 produced anterograde amnesia by their specific antagonism of the NMDA receptor complex.
Xu
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Department of Psychology, Grand Valley State University, Allendale, MI 49401, USA.
Klinger
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Davis
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R
D000647:Amnesia / Q000139:chemically induced* / Q000523:psychology; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology*; D003214:Conditioning, Classical / Q000187:drug effects; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D005239:Fear / Q000187:drug effects; D006054:Goldfish / Q000502:physiology*; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors / Q000633:toxicity; D011760:Pyrrolidinones / Q000494:pharmacology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*
D000927:Anticonvulsants; D011760:Pyrrolidinones; D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; C001369:1-hydroxy-3-amino-2-pyrrolidone