ROLE OF MITOGEN-ACTIVATED PROTEIN KINASE IN
NOENATAL MICE HYPOXIC ISCHEMIC CEREBRAL INSULT
Li Shuting,
Zheng Datong, Zhao Yingmin, Wu Weiling
Jiangjiayuan,
121, Nanjing 210011, China
Objective: Research on the effect
of hypoxia and ischemia in mitogen-activated protein kinase (MAPK)
pathway's activity in neonatal mice hippocampus to find the role of signal
transductionin during hypoxic and ischemic cerebral insult.
Method: According to Rice's
method, we use 7 days neonatal SD mice to make neonatal hypoxic and
ischemic cerebral insult model.
MAPK activity in hippocampus was assayed by phosphorylation of its
specific substrate myelin basic protein (MBP) after the fractionated by
MONO-Q anion-exchange chromatography.
Using liquid scintillation counting to determine 32P-labeled protein
and the activity was reported as picomoles of 32P per minute per
microgramme protein.
Result: 1. Identifing the MAPK
activity in hippocampus extracts of neonatal mice, collecting the eluting
liquid from MONO-Q fractionation, we found that the kinase activity was
recovered as a doublet, eluting at ~0.2 M NaCl, this peak can't be
inhibited by PKI (the inhibitor of PKA). So this peak is the MAPK activity peak. Compared with
control group, the activity of MAPK in hypoxic ischemic hippocampus was
significantly increased (p<0.01).
Table1. The effect of hypoxia & ischemia on the activity of MAPK
in neonatal hippocampus ( pmol/min/ug)
Control Experiment
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Number
13
15
Activity(x±s) 537.73±21.5 938.49±25.8
P
<0.01
Conclusion: Hypoxia and ischemia
stimulate the activity of MAPK in hippocampus and make it increasing
significantly. They may play
important role during the hypoxic and ischemic cerebral insult and its
prognosis.
Key word: Hypoxia and ischemia,
Mitogen-activated protein kinase (MAPK)