Climbing fiber deafferentation reduces insulin-like growth factor I (IGF-I) content in cerebellum.
The presence of insulin-like growth factor I (IGF-I) and its mRNA in adult rat cerebellum has recently been documented. Previous immunocytochemical studies showed prominent IGF-I-like staining in fibers around Purkinje cell somas. To determine the origin of this IGF-I input to the Purkinje cell we destroyed the inferior olivary complex by either 3-acetylpiridine administration or electrolytical lesions. In both types of lesions we found a similar significant depletion of IGF-I levels in cerebellum (40-50% of controls). No changes were found in cerebellar IGF-I receptors. These results suggest that almost half of the IGF-I content in cerebellum is provided by climbing fiber afferents arising from the inferior olivary complex.
Torres-Alemán
I
I
Laboratory of Cellular and Molecular Neuroendocrinology, Instituto Cajal, CSIC, Madrid, Spain.
Pons
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S
García-Segura
L M
LM
D000818:Animals; D002531:Cerebellum / Q000378:metabolism* / Q000502:physiology; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D009475:Neurons, Afferent / Q000502:physiology*; D009847:Olivary Nucleus / Q000166:cytology / Q000502:physiology; D011689:Purkinje Cells / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000378:metabolism; D017451:Receptors, Somatomedin; D013238:Stereotaxic Techniques
D011725:Pyridines; D011956:Receptors, Cell Surface; D017451:Receptors, Somatomedin; C010835:3-acetylpyridine; D007334:Insulin-Like Growth Factor I