The role of extracellular signal-regulated kinases in the neuroprotection of limb ischemic preconditioning.
To clarify the role of phosphorylated extracellular signal-regulated kinases (pERK1/2) in the neuroprotection of limb ischemic preconditioning (LIP) in rats, we investigated the expression of pERK1/2 using Western blot and flow cytometry in the hippocampus after LIP and the effect of pERK1/2 inhibitor PD 98059 on the neuroprotection of LIP against delayed neuronal death (DND) in the CA1 hippocampus normally induced by severe ischemic insult. It demonstrated that pERK1/2 in the hippocampus increased after LIP. In the CA1 hippocampus, ERK1/2 activation began to increase at 6h and reached peak at 12h after LIP, and decreased to sham level at 5d after LIP. On the other hand, in the CA3/DG, pERK1/2 enhanced at 1d, reached peak at 3d, and lasted to 5d after LIP. Pretreatment with PD 98059 before LIP blocked the neuroprotection of LIP in a dose-dependent manner. These findings supported that the upregulation of pERK1/2 in the CA1 hippocampus contributed to the neuroprotection of LIP against DND normally caused by the brain ischemic insult.
Jin
Rui-Li
RL
Department of Pathophysiology, Institute of Basic Medicine, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang 050017, PR China.
Li
Wen-Bin
WB
Li
Qing-Jun
QJ
Zhang
Min
M
Xian
Xiao-Hui
XH
Sun
Xiao-Cai
XC
Zhao
Hong-Gang
HG
Qi
Jie
J
D000818:Animals; D015153:Blotting, Western / Q000379:methods; D002545:Brain Ischemia / Q000201:enzymology / Q000503:physiopathology*; D016923:Cell Death / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000502:physiology*; D005121:Extremities / Q000098:blood supply*; D005419:Flavonoids / Q000494:pharmacology; D005434:Flow Cytometry / Q000379:methods; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006624:Hippocampus / Q000473:pathology; D019194:Ischemic Preconditioning; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D004791:Enzyme Inhibitors; D005419:Flavonoids; D048049:Extracellular Signal-Regulated MAP Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one