Changes of brain-derived neurotrophic factor mRNA and protein expression in the penumbra of rat cortex after focal cerebral ischemia/reperfusion

Objective To observe the mRNA and protein levels of brain-derived neurotrophic factor(BDNF)in the penumbra of rat cortex after focal cerebral ischemia/reperfusion(I/R).Methods The I/R rat models were established by middle cerebral artery occlusion(MCAO)method to observe the expression variation of BDNF mRNA and protein at 3,6,12h and 1,4,7d after I/R by in situ hybridization and immunochemistry method.Results The expressions of BDNF mRNA and protein in the penumbra region increased at 3h after reperfusion,and reached the peak at 12h,then decreased continuously after 3d(P0.05 or 0.01),and decreased to nomal level after 7d.Conclusion The mRNA and protein levels of BDNF increase in the penumbra of rat cortex after focal cerebral ischemia which suggests that it may protect neurons from apoptosis following cerebral ischemia.