Characteristic phosphorylation of the extracellular signal-regulated kinase pathway after kainate-induced seizures in the rat hippocampus.
Extracellular signal-regulated kinase (ERK) pathways play a crucial role in cell growth and long-lasting neuronal plasticity. Several studies have shown that phosphorylated-ERK (p-ERK) significantly increases after kainic acid (KA) administration. However, little or no information is available about the spatial distribution of p-ERK after KA-induced seizures. We herein show that KA-induced seizures significantly increase p-ERK in both neurons and astrocytes in rat brain using Western blots and immunohistochemistry. A strong immunoreactivity for p-ERK was induced in the dentate hilar neurons and CA3 neurons 30 mins and 6 hrs after KA injection. In addition, immunoreactivity for p-ERK was seen in astrocytes 6 hrs after KA injection. 72 hrs after KA injection, all pyramidal neurons had died. These findings suggest that the ERK pathway participates in the KA-induced neurotoxicity in the rat hippocampus.
Otani
N
N
Department of Neurosurgery, National Defense Medical College, Tokorozawa, Saitama, Japan. grd1405@gr.ndmc.ac.jp
Nawashiro
H
H
Yano
A
A
Katoh
H
H
Ohnuki
A
A
Miyazawa
T
T
Shima
K
K
D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D015153:Blotting, Western; D018690:Excitatory Amino Acid Agonists; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D007608:Kainic Acid; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000139:chemically induced* / Q000378:metabolism*; D013194:Staining and Labeling
D018690:Excitatory Amino Acid Agonists; D020928:Mitogen-Activated Protein Kinases; D007608:Kainic Acid