Enriched environment restores normal behavior while providing cytoskeletal restoration and synaptic changes in the hippocampus of rats exposed to an experimental model of depression

SIFONIOS L; TRINCHERO M; CERESETO M; FERRERO A; CLADOUCHÓS, MARÍA LAURA; FERNÁNDEZ MACEDO, GEORGINA; REINÉS A; WIKINSKI S

NEUROSCIENCE

Elsevier

Lugar: Estados Unidos; Año: 2009 vol. 164 p. 929 - 940

0306-4522

Abstract The exposure of rats to an enriched environment (EE) has several effects in common with the administration of antidepressants. However, therefs still little information about the molecular underpinnings of these effects in rats subjected to experimental models of depression. The aim of this work was to evaluate the effects of EE in rats exposed to the learned helplessness paradigm (LH), a well-known model of the disease. We found that 21 days of EE reverts the helpless behavior to normal in LH animals. Inmunohistochemical labeling showed that this effect was accompanied by normalization to control values of two structural proteins of hippocampal neurons: the light neurofilament subunit and the postsynaptic density 95 protein, which were decreased in LH animals housed in standard cages. The decrease in the presynaptic protein synaptophysin observed in LH animals remained unchanged after exposure to EE. There was no increase in neurogenesis as measured by quantification of double-labeled cells with 5-bromo-2L-deoxyuridine (BrdU) and the neuronal marker ƒÀ-Tubulin class III. These results show that EE may have behavioral, and synaptic effects in animals exposed to an experimental model of depression and that such actions seem to be independent from neurogenesis.