| Objects: This aim of the study was to investigate the improment of high-frequency rTMS on cognitive ability in rats with global cerebral ischemia.And to research the effect on hippocampal LFPs,meanwhile,to explore BNDF/TrkB signaling pathway on neuronal synaptic plasticity,provide a new basis for clinical treatment of cognitive dysfunction.Methods:(1)The SD rats were randomly divided into sham operation group(group SO),model control group(group MC),sham stimulation group(group Sham),real stimulation group(group rTMS),real stimulation+K252a group(group K252 a,given 50μg /Kg TrkB receptor blocker K252a).(2)Modle of rats with global cerebral ischemia were established by modified Pulsinelli four vascular occlusion.(3)The Corresponding groups were given magnetic stimulation and drug treatment.Morris water maze test was performed before surgery and after 14 days of high frequency rTMS intervention.(4)Using multi-channel in vivo recording technique acquisition LFPs of hippocampus in those rats,and analysis the power spectral density of theta(4-8Hz),gamma(30-100Hz)oscillations.(5).HE staining was used to observe the morphological changes of CA1 region,and the expression of BDNF、p-TrkB were detected by immunohistochemistry and WB.Results:(1)Results of morris water maze test:After the intervention of high-frequency rTMS,the average escape latency of rTMS group was lessthan MC、Sham、K252a groups(P<0.05);the times of crossing the platform and the platform quadrant swimming time,rTMS group compared with MC、Sham、K252a groups was shortened(P<0.05).(2)Results of power spectral density analysis: power spectral density analysis showed that compared with the SOgroup,the power spectrum densitytheta of gamma and theta oscillations of MC group were decreased(P<0.05);compared with MC、Sham groups,rTMS group was increased(P<0.05);compared with K252 a group,rTMS group was increased(P<0.05).(3)Results of HE staining: the cells in hippocampal CA1 area of SO group were large and round,neatly arranged,cytoplasm and nucleus visible;MC 、Sham、K252a groups were disorder,less numbers,cytoplasmic stain eosinophilic,and,different degrees of degeneration and necrosis.Compared with MC、Sham、K252a groups,the degree of group rTMS was lighter.(4)Results of immunohistochemistry:the SO group expressed few BNDF and p-TrkB positive cells;compared with MC 、 Sham、rTMS、K252a groups,group SO had more positive cells expressed,there was a significant difference between rTMS group,K252 a group and Sham group(P<0.05).(5)Results of WB: the protein gray ratio of BDNF and p-TrkB protain,SO group had less than MC、Sham、rTMS groups(P<0.05).Conclusion:(1)High-frequency rTMS Improved cognitive ablity of rats with lobal cerebral ischemia through increasing the LFPs in the hippocampal CA1 area.(2)High-frequency rTMS maight affect the plasticity of synaptic structure and function by regulating the BDNF/TrkB signal pathway of hippocampal CA1 region in rats with global cerebral ischemia.(3)High-frequency rTMS maight improve cognitive function by enhancingLFPs and regulating BDNF/TrkB signaling pathway in hippocampus CA1 of rats with global cerebral ischemia. |
PDF Full Text Request