Visual input regulates the expression of basic fibroblast growth factor and its receptor.
Emerging evidence indicates that the expression of trophic factors in the brain is regulated in an activity-dependent manner, which suggests an involvement of trophic factors in events controlled by input activity. We have investigated the possibility that visual sensory input impacts the expression of basic fibroblast growth factor and its receptor in the brain. Rats were maintained for seven days in darkness and then re-exposed to normal illumination for 0, 1, 3 or 6 h. We assessed relative levels of basic fibroblast growth factor and fibroblast growth factor receptor messenger RNAs using nuclease protection assays, and examined possible changes in the phenotypic expression of basic fibroblast growth factor and its receptor using immunohistochemistry. There was a significant decrease in levels of basic fibroblast growth factor and fibroblast growth factor receptor messenger RNAs as a result of dark rearing, and levels of messenger RNAs increased progressively with light re-exposure. Changes in messenger RNAs were observed primarily in the cerebral cortex (caudal portion) and were accompanied by alterations in the staining intensity and density of cells exhibiting basic fibroblast growth factor and fibroblast growth factor receptor phenotypes. Regulation of the basic fibroblast growth factor system by sensory input suggests that basic fibroblast growth factor, and perhaps other trophic factors, are mediators of the effects of experience on the structure and function of the CNS.
Gómez-Pinilla
F
F
Institute for Brain Aging and Dementia and Department of Neurology, University of California, Irvine 92697-4540, USA.
Choi
J
J
Ryba
E A
EA
D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism; D003624:Darkness; D016222:Fibroblast Growth Factor 2 / Q000235:genetics / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism; D010775:Photic Stimulation; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D051497:Receptor, Fibroblast Growth Factor, Type 2; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics / Q000378:metabolism*; D014018:Tissue Distribution / Q000502:physiology; D014795:Visual Pathways / Q000502:physiology*
D012333:RNA, Messenger; D017468:Receptors, Fibroblast Growth Factor; D016222:Fibroblast Growth Factor 2; C496356:Fgfr2 protein, rat; D020794:Receptor Protein-Tyrosine Kinases; D051497:Receptor, Fibroblast Growth Factor, Type 2