Dizocilpine-induced neuropathological changes in rat retrosplenial cortex are reversed by subsequent clozapine treatment.
In this study, we examined the effect of post-treatment with clozapine on the neuropathological changes in the rat retrosplenial cortex induced by the administration of non-competitive NMDA receptor antagonist dizocilpine ((+)-MK-801). The maximal increase in vacuolized neurons, which are representative of neuropathology, was observed 4 hours after a single injection of dizocilpine (0.5 mg/kg s.c.), with a complete reversal of the neuropathology after 16-24 hours. The administration of clozapine (10 mg/kg, i.p.,) 4 hours after the administration of dizocilpine significantly decreased the number of vacuolized neurons in the retrosplenial cortex 6, 8 or 10 hours after administration of dizocilpine, compared to vehicle-treated animals. Furthermore, the administration of clozapine (5, 10 or 20 mg/kg i.p.) 4 hours after the administration of dizocilpine produced a significant decrease in the number of vacuolized neurons in the retrosplenial cortex in a dose-dependent manner when measure 6 hours post-dizocilpine. These results show that neuropathological changes in the rat retrosplenial cortex produced by dizocilpine can be attenuated by post-treatment with clozapine.
Hashimoto
K
K
Tokyo Laboratories, Yoshitomi Pharmaceutical Industries, Ltd., Iruma, Saitama, Japan. hashimoto_kenji@yoshitomi.co.jp
Fujimura
M
M
Yamagami
K
K
D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects* / Q000473:pathology; D003024:Clozapine / Q000494:pharmacology*; D016291:Dizocilpine Maleate / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D018691:Excitatory Amino Acid Antagonists / Q000633:toxicity*; D005260:Female; D008032:Limbic System / Q000187:drug effects / Q000473:pathology; D009422:Nervous System Diseases / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D014617:Vacuoles / Q000473:pathology
D014150:Antipsychotic Agents; D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate; D003024:Clozapine