Brain sciences
August 25, 2024
Ana Carolina Dutra-Tavares, Luciana Araújo Couto, Thainá P Souza et al.
In a mouse model of schizophrenia induced by phencyclidine, the order in which nicotine (a surrogate for smoking) is introduced matters for the behavioral outcomes. Nicotine given before phencyclidine potentiated locomotor sensitization, a behavior linked to psychosis. Nicotine given after phencyclidine worsened a schizophrenia-like deficit in pre-pulse inhibition, but only in male mice. Neither sequence affected rearing, a control behavior. The findings suggest that whether smoking precedes schizophrenia or vice versa produces distinct effects on the brain and behavior, which may help identify mechanisms underlying the high comorbidity between smoking and schizophrenia.
Psychopharmacology
October 1, 2023
Ana Carolina Dutra-Tavares, Thainá P Souza, Juliana O Silva et al.
Sex differences in schizophrenia may originate early in life. Mice given phencyclidine (PCP) on postnatal days 7, 9, and 11 showed dose-dependent deficits in open field, social interaction, and prepulse inhibition tests during late adolescence (PN48-50). Males were more susceptible to these behavioral deficits and had reduced GluN1 subunit expression in the frontal cortex at early adolescence (PN30). By late adolescence (PN50), cortical GluN1 was increased in both sexes, while PCP increased cortical and decreased hippocampal PSD-95 in females. The antipsychotic olanzapine failed to mitigate most PCP-evoked alterations and sometimes worsened deficits, suggesting its use during adolescence needs further evaluation.
Toxicology and applied pharmacology
December 1, 2022
Ana Carolina Dutra-Tavares, Anais Bandeira-Martins, Juliana O Silva et al.
In adolescent mice, nicotine exposure did not worsen and may have even ameliorated psychotic-like behavior induced by phencyclidine, a model of psychosis. The antipsychotic drug raclopride prevented the development of this behavior, and nicotine temporarily boosted raclopride's inhibitory effect. Nicotine history shortened the expression of sensitized behavior after withdrawal. The findings suggest that nicotine may transiently improve the efficacy of antipsychotic medication through mechanisms involving dopamine D2 receptors.