Open AccessEnvironmental enrichment induces behavioural disturbances in neuropeptide Y knockout mice
Author(s) -
Florian Reichmann,
Vanessa Wegerer,
Piyush Jain,
Raphaela Mayerhofer,
Ahmed M. Hassan,
Esther E. Fröhlich,
Elisabeth Bock,
Elisabeth Pritz,
Herbert Herzog,
Peter Holzer,
Gerd Leitinger
Publication year - 2016
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep28182
Subject(s) - neuropeptide y receptor , environmental enrichment , endocrinology , medicine , hippocampal formation , knockout mouse , hippocampus , neuropeptide , anxiolytic , amygdala , neurotrophic factors , stimulation , brain derived neurotrophic factor , glucocorticoid receptor , receptor , biology , glucocorticoid , chemistry
Environmental enrichment (EE) refers to the provision of a complex and stimulating housing condition which improves well-being, behaviour and brain function of laboratory animals. The mechanisms behind these beneficial effects of EE are only partially understood. In the current report, we describe a link between EE and neuropeptide Y (NPY), based on findings from NPY knockout (KO) mice exposed to EE. Relative to EE-housed wildtype (WT) animals, NPY KO mice displayed altered behaviour as well as molecular and morphological changes in amygdala and hippocampus. Exposure of WT mice to EE reduced anxiety and decreased central glucocorticoid receptor expression, effects which were absent in NPY KO mice. In addition, NPY deletion altered the preference of EE items, and EE-housed NPY KO mice responded to stress with exaggerated hyperthermia, displayed impaired spatial memory, had higher hippocampal brain-derived neurotrophic factor mRNA levels and altered hippocampal synaptic plasticity, effects which were not seen in WT mice. Accordingly, these findings suggest that NPY contributes to the anxiolytic effect of EE and that NPY deletion reverses the beneficial effects of EE into a negative experience. The NPY system could thus be a target for “enviromimetics”, therapeutics which reproduce the beneficial effects of enhanced environmental stimulation.