Attention and memory in aged rats: Impact of lifelong environmental enrichment.
Aged rodents exhibit memory and attention dysfunctions. Environmental enrichment (EE) attenuates memory impairments. Whether it may reduce attention deficits is not known. At the age of 1 month, Long-Evans female rats were placed in standard or EE conditions and tested after 3 (young), 12 (middle-aged) or 24 (aged) months of differential housing. Spatial reference memory was assessed in a water-maze task. Attention performance was evaluated in the five-choice serial reaction time (5-CSRT) task. EE improved spatial memory at all ages, but did not ameliorate 5-CSRT performance in young and middle-aged rats; it prevented, however, the degradation of attention performances detected in aged rats. The number of ChAT (+30 to +64%)- and p75(NTR)-positive (+35 to +44%) neurons was higher in the basal forebrain of aged enriched vs. standard rats, suggesting their EE-mediated protection. The weaker deficit of attention found in aged EE rats might be linked to a better survival in the very long term of neurons in the basalo-cortical system.
Harati
Hayat
H
Laboratoire d'Imagerie et de Neurosciences Cognitives, Université de Strasbourg, IFR 37 de Neurosciences, GDR 2905 du CNRS, 12 rue Goethe, F-67000 Strasbourg, France.
Majchrzak
Monique
M
Cosquer
Brigitte
B
Galani
Rodrigue
R
Kelche
Christian
C
Cassel
Jean-Christophe
JC
Barbelivien
Alexandra
A
D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001288:Attention / Q000502:physiology*; D001835:Body Weight / Q000502:physiology; D001921:Brain / Q000378:metabolism; D002452:Cell Count; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D004777:Environment; D005260:Female; D006799:Housing, Animal; D007150:Immunohistochemistry; D018782:Maze Learning / Q000502:physiology*; D008568:Memory / Q000502:physiology*; D009043:Motor Activity / Q000502:physiology; D009474:Neurons / Q000378:metabolism; D010320:Parvalbumins / Q000378:metabolism; D051381:Rats; D020318:Rats, Long-Evans; D011930:Reaction Time / Q000502:physiology; D020800:Receptor, Nerve Growth Factor / Q000378:metabolism; D012044:Regression Analysis
D010320:Parvalbumins; D020800:Receptor, Nerve Growth Factor; D002795:Choline O-Acetyltransferase