Phencyclidine-induced cognitive deficits in mice are improved by subsequent subchronic administration of tropisetron: Role of alpha 7 nicotinic receptors

Department of Psychiatry, Chiba University, Tiba, Chiba, Japan
European Journal of Pharmacology (Impact Factor: 2.68). 01/2007; 553(1-3):191-5. DOI: 10.1016/j.ejphar.2006.09.055
Source: PubMed

ABSTRACT We examined the effects of tropisetron, a 5-hydroxytryptamine (5-HT(3)) receptor antagonist and alpha7 nicotinic receptor agonist, on cognitive deficits in mice after repeated administration of the NMDA receptor antagonist phencyclidine (PCP). PCP (10 mg/kg/day for 10 days)-induced cognitive deficits were significantly improved by subsequent subchronic (2 weeks) administration of tropisetron, but not ondansetron. Effects of tropisetron were significantly antagonized by co-administration of the alpha7 nicotinic receptor antagonist methyllycaconitine, suggesting the role of alpha7 nicotinic receptors in the active mechanisms of tropisetron. These findings suggest that tropisetron could be a potential therapeutic drug for cognitive deficits in schizophrenic patients.

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