Different agonists of the alpha7 nicotinic acetylcholine receptors (nAChRs) are currently being evaluated as possible treatments for different conditions such as Alzheimer’s and Parkinson’s diseases as well as cognitive symptoms in schizophrenic patients. In preclinical studies, the nicotinic agonist PNU-282987 (PNU) improves cognition and induces antidepressant effects. Prior research in our laboratory suggests that acute administration of this drug may influence behavioral profile displayed by mice in the elevated plus maze (EPM), although there are very few data on the behavioral actions of low doses of PNU in rodents maintained in different housing conditions. The main aim of the current study was to compare the effects of low doses of PNU on anxiety-like behavior and motor and exploratory activities in mice reared in standard environments (SE) versus enriched environments (EE) in two experimental studies. 64 Naval Medical Research Institute (NMRI) male mice were employed in the first study. One group of 32 mice was housed in SE conditions and another group of 32 mice in EE conditions. After 3 weeks (post-natal day 50), the mice received an acute treatment with low doses of PNU (1.25, 2.5, 5 mg/kg) and were evaluated in an actimeter. In the second study, a similar procedure was carried out and mice were evaluated in the EPM and the hole-board (HB) after acute treatment with the same doses of PNU. Results indicated that mice housed in EE displayed lower motor activity than SE mice during the 16-20 min period (p < 0.05) whereas the factor ‘PNU Treatment’ did not reach statistical significance. In the EPM and HB tasks, no significant effects of PNU treatment or housing conditions were obtained. Data obtained may have implications in studies evaluating how the behavioral and neurochemical effects of different drugs of abuse could possibly be modulated by EE. These results could also be of interest in the context of preclinical studies aimed to develop new treatments for neurodegenerative diseases or mental disorders.
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