Age-related upregulation of insulin-like growth factor receptor type I in rat cerebellum.
We investigated age-related changes in insulin-like growth factor-I (IGF-I) receptor localization in the cerebellum using immunohistochemical staining. In adult rats, no immunoreactivity for IGF-I receptor was found in any layers of cerebellar cortex. In contrast, IGF-I receptor immunoreactivity was found in the cerebellar cortex of aged rats. The most prominent labeling was localized in the Purkinje cell layers and molecular layers. The cerebellar output neurons showed little immunoreactivity for IGF-I receptor in the nucleus medialis, interpositus and lateralis of adult rats. In aged cerebellar nuclei, IGF-I receptor immunoreactivity was observed in the surrounding neuropil. The first demonstration of upregulation of IGF-I receptor in aged rat cerebellum suggests that IGF-I may promote the survival of a degenerated population of the Purkinje neurons by increases in IGF-I receptor expression during aging.
Chung
Yoon Hee
YH
Department of Anatomy, Seoul National University College of Medicine, 28 Yongon-Dong, Chongno-Gu, Seoul 110-799, South Korea. yoohee2@snu.ac.kr
Shin
Chung Min
CM
Joo
Kyeung Min
KM
Kim
Myeung Ju
MJ
Cha
Choong Ik
CI
D000375:Aging / Q000502:physiology*; D000818:Animals; D002531:Cerebellum / Q000737:chemistry / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000032:analysis / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D017526:Receptor, IGF Type 1 / Q000032:analysis / Q000096:biosynthesis*; D015854:Up-Regulation / Q000502:physiology*
D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1