Immunoreactive Akt, PI3-K and ERK protein kinase expression in ischemic rat brain.
In order to clarify the role of protein kinases in ischemic brain injury, the spatiotemporal expression of immunoreactive serine-threonine kinase Akt, phosphatidylinositol 3-kinase (PI3-K) and extracellular signal-regulated kinase (ERK) were examined at 3, 8, or 24 h after permanent middle cerebral artery occlusion (MCAO) in rats. Weak staining for these protein kinases was found in both cortical and caudate neurons in sham controls. The staining for Akt-1 and PI3-K was increased at 3-8 h in the ischemic penumbral region and declined at 24 h. A slight induction of these kinases was observed in the ischemic core region. Robust expression of ERK was noted at 3-8 h in most neurons in the area of ischemia. At 24 h, ERK continued to be expressed in the ischemic penumbra, but decreased in the ischemic core. These findings suggest that the signaling for Akt and PI3-K are different from the ERK dependent signal transduction during ischemic brain injury.
Kitagawa
H
H
Department of Neurology, Okayama University Medical School, Japan.
Warita
H
H
Sasaki
C
C
Zhang
W R
WR
Sakai
K
K
Shiro
Y
Y
Mitsumoto
Y
Y
Mori
T
T
Abe
K
K
D000818:Animals; D002545:Brain Ischemia / Q000201:enzymology*; D002421:Caudate Nucleus / Q000201:enzymology*; D002540:Cerebral Cortex / Q000201:enzymology*; D019084:Fluorescent Antibody Technique, Indirect; D020244:Infarction, Middle Cerebral Artery / Q000201:enzymology; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000096:biosynthesis*; D019869:Phosphatidylinositol 3-Kinases / Q000096:biosynthesis*; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D051057:Proto-Oncogene Proteins c-akt; D051381:Rats; D017208:Rats, Wistar
D020928:Mitogen-Activated Protein Kinases; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011505:Protein-Tyrosine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; C494920:Akt1 protein, rat