An enriched environment restores normal behavior while providing cytoskeletal restoration and synaptic changes in the hippocampus of rats exposed to an experimental model of depression.
The exposure of rats to an enriched environment (EE) has several effects in common with the administration of antidepressants. However, there is still little information about the molecular underpinnings of these effects on rats subjected to experimental models of depression. The aim of this research was to evaluate the effects of EE on rats exposed to the learned helplessness paradigm (LH), a well-known model of the disease. We found that a 21 day exposure to EE reverts helplessness behavior to normal in LH animals. Inmunohistochemical labeling showed that this effect was accompanied by normalization of two structural proteins of hippocampal neurons to control values: the light neurofilament subunit (NFL) and the postsynaptic density 95 (PSD-95) protein, which were decreased in LH animals housed in standard cages. The decrease in the presynaptic protein synaptophysin (SYN) 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'-deoxyuridine (BrdU) and the neuronal marker beta-tubulin class III. These results show that EE may have behavioral and synaptic effects on animals exposed to an experimental model of depression, and that such actions seem to be independent from neurogenesis.
Sifonios
L
L
Instituto de Investigaciones Farmacológicas (ININFA-UBA/CONICET), Junín 956, 5 degrees piso, (1113) Ciudad de Buenos Aires, Argentina. lsifonios@ffyb.uba.ar
Trinchero
M
M
Cereseto
M
M
Ferrero
A
A
Cladouchos
M L
ML
Macedo
G F
GF
Reinés
A
A
Wikinski
S
S
D000818:Animals; D001973:Bromodeoxyuridine; D003599:Cytoskeleton / Q000378:metabolism* / Q000648:ultrastructure; D003866:Depressive Disorder / Q000378:metabolism* / Q000503:physiopathology / Q000628:therapy*; D004195:Disease Models, Animal; D000076122:Disks Large Homolog 4 Protein; D004780:Environment, Controlled; D005106:Exploratory Behavior / Q000502:physiology; D006380:Helplessness, Learned; D006624:Hippocampus / Q000378:metabolism* / Q000648:ultrastructure; D007150:Immunohistochemistry; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D016900:Neurofilament Proteins / Q000378:metabolism; D055495:Neurogenesis; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000378:metabolism / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D013569:Synapses / Q000378:metabolism* / Q000648:ultrastructure; D009435:Synaptic Transmission / Q000502:physiology; D016708:Synaptophysin / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism
D000076122:Disks Large Homolog 4 Protein; C501449:Dlg4 protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D016900:Neurofilament Proteins; D016708:Synaptophysin; D014404:Tubulin; C044882:neurofilament protein L; D001973:Bromodeoxyuridine