In contrast to neuronal NOS-I, the inducible NOS-II expression in aging brains is modifled by enriched environmental conditions.
Changes in the expression of the nitric oxide synthase isoforms (NOS) have been implicated in age-related neurodegeneration, although mechanisms responsible for specific differences such as reduced cognitive and motor functions are not well understood. Immunohistochemical examination of the age-dependent NOS-I and NOS-II expression in aging rats at 3, 12, 24, 36 months of age as well as in 36 months old rats who spent their last 3 months in an enriched environment, revealed a significant decrease in NOS-I expression with aging. In contrast, NOS-II increased at 36 months. Old rats kept under enriched environmental conditions, however, showed strongly reduced NOS-II expression. These results indicate that both NOS-I and II may contribute to age-related degenerative processes, but in contrast to NOS-I the age-dependent changes of NOS-II are reduced or even reversed by stimulating environmental conditions.
Hilbig
Heidegard
H
Institut für Anatomie, Universität Leipzig, Germany.
Holler
Josefin
J
Dinse
Hubert R
HR
Bidmon
Hans-Jïrgen
HJ
D000375:Aging / Q000378:metabolism*; D000818:Animals; D002452:Cell Count; D002540:Cerebral Cortex / Q000737:chemistry / Q000201:enzymology*; D002678:Chimera; D004777:Environment; D007091:Image Processing, Computer-Assisted; D007124:Immunoenzyme Techniques; D008297:Male; D009252:NADPH Dehydrogenase / Q000032:analysis / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000201:enzymology; D019001:Nitric Oxide Synthase / Q000032:analysis / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D051381:Rats; D011914:Rats, Inbred BN; D011916:Rats, Inbred F344
D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; C496322:Nos1 protein, rat; D009252:NADPH Dehydrogenase