New treatment mechanisms for sch...(nt of depression. In the second art...)

In the second article, Hashimoto and colleagues demonstrated that repeated administration of the N-methyl-D-aspartate (NMDA) receptor antagonist phencyclidine (PCP) decreased the density of 7 nicotinic receptors (7 nAChRs) in the mouse brain, and that the novel 7 nAChR agonist SSR180711 could ameliorate PCP-induced cognitive deficits in mice. According to Kenji Hashimoto, Ph.D., head author for this study, the impetus for this study came from the fact that accumulating evidence suggests that 7 nicotinic receptors, a subtype of nicotinic receptors, are a most attractive target for novel therapeutic drugs of neuropsychiatric diseases including schizophrenia and Alzheimers disease. Behavioral abnormalities in animals after repeated administration of the NMDA receptor antagonist phencyclidine (PCP) have been used an animal model of schizophrenia. These findings suggest that 7 nAChR agonists including SSR180711 could be potential therapeutic drugs for cognitive deficits in schizophrenic patients.

In the third investigation, Semenova and colleagues show that a recently discovered brain receptor for serotonin (5-HT7) might be of importance for understanding certain aspects of schizophrenia. Their study focused on sensory input processing, which is often impaired in schizophrenia, and finds that blockade of this particular serotonin receptor in mice alleviates this impairment. Peter B. Hedlund, M.D., Ph.D., senior author, notes: Certain pharmaceuticals used to treat schizophrenia interact with this receptor. Our results indicate that especially so-called atypical antipsychotics may promiscuously exert some of their beneficial effects through the 5-HT7 receptor. Further exploration of this receptor as a treatment target may lead to more specific and better medications for disorders such as schizophrenia.

John H. Krystal, M.D., Editor of Biological Psychiatry and affiliated with both Yale
'/>"/>