title: Expression of alpha 4-1 and alpha 5 nicotinic cholinoceptor mRNA in the aging rat cerebral cortex.
abstract: Although important in neurodegeneration, systematic studies of nicotinic acetylcholine receptor expression in normal aging human brains are difficult to perform. We have studied the expression of nicotinic receptor alpha 4-1 and alpha 5 mRNA in the frontal and parietal isocortex of 3- (young adult), 24- (late middle aged), and 33-month-old (old) rats by nonisotopic in situ hybridization. In all groups transcripts were mainly present in layer II/III and V pyramidal neurons. The numerical densities of alpha 4-1 mRNA-containing neurons with respect to those of cresyl violet-stained neurons decreased with aging in the rat frontal and parietal cortex, while those of alpha 5 mRNA-containing neurons were not affected. These findings point to an age-related decrease of the percentages of numerical densities of alpha 4-1 mRNA-containing neurons, which has to be taken into account as a possible substrate for the well-known decrease of nicotine binding sites in the aging cerebral cortex.
authors.affiliation: Institut II für Anatomie, Universität zu Köln, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Birtsch
authors.forename: A
authors.initials: A
authors.lastname: Wevers
authors.forename: J
authors.initials: J
authors.lastname: Traber
authors.forename: A
authors.initials: A
authors.lastname: Maelicke
authors.forename: W
authors.initials: W
authors.lastname: Bloch
authors.forename: H
authors.initials: H
authors.lastname: Schröder
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011978:Receptors, Nicotinic / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D011978:Receptors, Nicotinic