Region-specific alterations in insulin-like growth factor receptor type I in the cerebral cortex and hippocampus of aged rats.
In the present study, we investigated age-related changes in IGF-I receptor localization in the cerebral cortex and hippocampus of Sprague-Dawley rats using immunohistochemistry. In the cerebral cortex of adult rats, weakly stained cells were seen in layers II-III and layer V/VI in several cortical regions. In aged rats, there was a significant increase in IGF-I receptor immunoreactivity in the pyramidal cells in the same cortical regions. In the hippocampus of adult rats, several moderately stained neurons were seen in CA1-3 areas and the dentate gyrus. Levels of IGF-I receptor protein increased substantially with age in the CA3 area of the hippocampus. Our first morphological data concerning the differential regulation of IGF-I receptors in aged cerebral cortex and hippocampus may provide insights into age-related changes in trophic support as well as basic knowledge required for the study of neurodegenerative diseases such as Alzheimer's disease.
Department of Anatomy, Seoul National University College of Medicine, 28 Yongon-Dong, Chongno-Gu, South Korea.
Yoon Hee
YH
Chung
Chung Min
CM
Shin
Kyeung Min
KM
Joo
Myeung Ju
MJ
Kim
Choong Ik
CI
Cha
D000375:Aging / Q000378:metabolism*; D000818:Animals; D001369:Axons / Q000378:metabolism; D002540:Cerebral Cortex / Q000254:growth & development / Q000378:metabolism*; D018891:Dentate Gyrus / Q000254:growth & development / Q000378:metabolism; D006624:Hippocampus / Q000254:growth & development / Q000378:metabolism*; D007150:Immunohistochemistry; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D017526:Receptor, IGF Type 1 / Q000378:metabolism*
D012333:RNA, Messenger; D017526:Receptor, IGF Type 1