Age-related changes in erythropoietin immunoreactivity in the cerebral cortex and hippocampus of rats.
Although oxidative stress may influence the fluid properties of blood, resulting in a potential decrement in blood flow and oxygen delivery to the brain during aging, very little is known about age-related changes in Epo expression. Therefore, we examined age-related changes in Epo expression in the cerebral cortex and hippocampus with an immunohistochemical technique. In aged rats, there was a significant decrease in Epo immunoreactivity in the pyramidal cells in the cortical regions. In the hippocampus of adult rats, a distinct immunoreactivity pattern was observed in the CA1-3 areas and dentate gyrus. In aged hippocampus, Epo immunoreactivity was significantly deceased in the pyramidal layer of CA1 regions, and the granule cell layer of dentate gyrus. It was noted that there was distinct pattern of Epo immunoreactivity in the pyramidal layer of CA2-CA3 region of aged rats. Epo immunoreactivity was relatively strong, but was observed only in the periphery of the cytoplasm. The first demonstration of age-related decreases in Epo expression in the cerebral cortex and hippocampus may provide useful data for investigating the pathogenesis of age-related neurodegenerative diseases, suggesting that age-related decreases in Epo may contribute to degenerative events following age-related decreases in brain flow and oxygen supply.
Chung
Yoon Hee
YH
Department of Anatomy, College of Medicine, Chung-Ang University, 221 Heukseok-Dong, Dongjak-Gu, Seoul 156-756, South Korea.
Kim
Soo In
SI
Joo
Kyeung Min
KM
Kim
Yang Soo
YS
Lee
Won Bok
WB
Yun
Kyu Wol
KW
Cha
Choong Ik
CI
D000375:Aging / Q000378:metabolism*; D000818:Animals; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure; D018891:Dentate Gyrus / Q000166:cytology / Q000378:metabolism; D015536:Down-Regulation / Q000502:physiology*; D004921:Erythropoietin / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D008569:Memory Disorders / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D019636:Neurodegenerative Diseases / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D018696:Neuroprotective Agents / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D017966:Pyramidal Cells / Q000166:cytology / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000502:physiology
D018696:Neuroprotective Agents; D004921:Erythropoietin