Phosphorylated extracellular signal-regulated kinase 1/2 immunoreactivity and its protein levels in the gerbil hippocampus during normal aging.
Phosphorylated extracellular signal-regulated kinase (pERK) mediates neuronal synaptic plasticity, long-term potentiation, and learning and memory in the hippocampus. In this study, we examined pERK1/2 immunoreactivity and its protein level in the gerbil hippocampus at various ages. In the postnatal month 1 (PM 1) group, very weak pERK1/2 immunoreactivity was detected in the hippocampus. In the CA1 region, pERK1/2 immunoreactivity was considerably increased in the stratum pyramidale in the PM 6 group. Thereafter, pERK1/2 immunoreactivity was decreased. In the CA2/3 region, pERK1/2 immunoreactivity increased in an age-dependent manner until PM 12. Thereafter, numbers of pERK1/2-immunoreactive neurons were decreased. However, in the mossy fiber zone, pERK1/2 immunostaining became stronger with age. In the dentate gyrus, a few pERK1/2-immunoreactive cells were observed until PM 12. In the PM 18 and 24 groups, numbers of pERK1/2-immunoreactive cells were increased, especially in the polymorphic layer. In Western blot analysis, pERK1/2 level in the gerbil hippocampus was increased with age. These results indicate that total pERK1/2 levels are increased in the hippocampus with age. However pERK1/2 immunoreactivity in subregions of the gerbil hippocampus was changed with different pattern during normal aging.
Lee
Choong Hyun
CH
Department of Anatomy and Neurobiology, and Institute of Neurodegeneration and Neuroregeneration, College of Medicine, Hallym University, Chuncheon, 200-702, Korea.
Yoo
Ki-Yeon
KY
Park
Ok Kyu
OK
Choi
Jung Hoon
JH
Kang
Il-Jun
IJ
Bae
Eunjoo
E
Kim
Sung Koo
SK
Hwang
In Koo
IK
Won
Moo-Ho
MH
D000375:Aging; D000818:Animals; D015153:Blotting, Western; D018891:Dentate Gyrus / Q000166:cytology / Q000201:enzymology / Q000254:growth & development; D005849:Gerbillinae; D006624:Hippocampus / Q000166:cytology / Q000201:enzymology* / Q000254:growth & development; D007150:Immunohistochemistry; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D009474:Neurons / Q000201:enzymology; D010766:Phosphorylation
D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3