Attenuation of c-Fos basal expression in the cerebral cortex of aged rat.
Cellular immediate early genes (IEG) such as c-fos were originally defined as rapid and transient inducible gene, but their products show a varying degree of basal expression in the brain of normal animals, suggesting that they also play a role in the transcriptional control under physiological conditions. In this study, we used an immunohistochemical method to investigate changes in the number of c-Fos-immunoreactive cells in the cerebral cortex and hippocampal formation of the aged rat. There was a remarkable decrease in the number of c-Fos-immunoreactive cells in the piriform and temporal cortex of aged rats compared with young adult rats. There was a slight decrease in the number of c-Fos-immunoreactive cells in the parietal cortex of aged rat. In the hippocampal complex, there were also decreases in the number of c-Fos-immunoreactive cells in aged rat; the degree of decrease was most prominent in the dentate gyrus. This report provides the first morphological evidence for decreased levels of basal c-Fos expression in some cerebral cortical areas and in the hippocampal complex of aged rats.
Lee
Y I
YI
Department of Anatomy, College of Medicine, Seoul National University, Korea.
Park
K H
KH
Baik
S H
SH
Cha
C I
CI
D000375:Aging / Q000378:metabolism*; D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D016762:Genes, fos / Q000235:genetics*; D006624:Hippocampus / Q000378:metabolism; D007150:Immunohistochemistry; D051381:Rats; D017207:Rats, Sprague-Dawley