TRANSCRIPTION SUPPORTS AGE-RELATED INCREASES OF GFAP GENE-EXPRESSION IN THE MALE-RAT BRAIN

During aging, rodent and human brains show progressive increases in th e levels of glial fibrillary acidic protein (GFAP) mRNA and protein. T he role of transcription was investigated by in situ hybridization, us ing an intron-containing cRNA probe as a measure of primary GFAP trans cripts. We found parallel age-related increases in GFAP intron RNA in the hippocampus, internal capsule, and corpus callosum of 3 versus 24 month old male F344 rats. We conclude that increased transcription sup ports the age-related increase of GFAP mRNA and protein. GFAP is a uni que example of a gene that shows increased expression during aging in contrast to the decreased transcription of certain genes reported in n on-neural tissues.