title: Decreased insulin-like growth factor-I and its receptor expression in the hippocampus and somatosensory cortex of the aged mouse.
abstract: Insulin-like growth factor-I (IGF-I) is a multifunctional polypeptide and has diverse effects on brain functions. In the present study, we compared IGF-I and IGF-I receptor (IGF-IR) immunoreactivity and their protein levels between the adult (postnatal month 6) and aged (postnatal month 24) mouse hippocampus and somatosensory cortex. In the adult hippocampus, IGF-I immunoreactivity was easily observed in the pyramidal cells of the stratum pyramidale in the hippocampus proper and in the granule cells of the granule cell layer of the dentate gyrus. In the adult somatosensory cortex, IGF-I immunoreactivity was easily found in the pyramidal cells of layer V. In the aged groups, IGF-I expression was dramatically decreased in the cells. Like the change of IGF-I immunoreactivity, IGF-IR immunoreactivity in the pyramidal and granule cells of the hippocampus and in the pyramidal cells of the somatosensory cortex was also markedly decreased in the aged group. In addition, both IGF-I and IGF-IR protein levels were significantly decreased in the aged hippocampus and somatosensory cortex. These results indicate that the apparent decrease of IGF-I and IGF-IR expression in the aged mouse hippocampus and somatosensory cortex may be related to age-related changes in the aged brain.
authors.affiliation: Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan, 330-714, South Korea.
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Lee
authors.forename: Ji Hyeon
authors.initials: JH
authors.lastname: Ahn
authors.forename: Joon Ha
authors.initials: JH
authors.lastname: Park
authors.forename: Bing Chun
authors.initials: BC
authors.lastname: Yan
authors.forename: In Hye
authors.initials: IH
authors.lastname: Kim
authors.forename: Dae Hwan
authors.initials: DH
authors.lastname: Lee
authors.forename: Jeong-Hwi
authors.initials: JH
authors.lastname: Cho
authors.forename: Bai Hui
authors.initials: BH
authors.lastname: Chen
authors.forename: Jae-Chul
authors.initials: JC
authors.lastname: Lee
authors.forename: Jun Hwi
authors.initials: JH
authors.lastname: Cho
authors.forename: Yun Lyul
authors.initials: YL
authors.lastname: Lee
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
authors.forename: Il-Jun
authors.initials: IJ
authors.lastname: Kang
mesh_terms: D000375:Aging / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D005786:Gene Expression Regulation; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D017526:Receptor, IGF Type 1 / Q000096:biosynthesis*; D013003:Somatosensory Cortex / Q000378:metabolism* / Q000473:pathology
chemical_list: C519530:insulin-like growth factor-1, mouse; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1