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OBJECTIVE@#To observe the effects of electroacupuncture (EA) on sympathetic nerve-related substance in myocardial tissue in mice with myocardial ischemia (MI), and to explore its possible mechanism.@*METHODS@#Thirty adult male C57BL/6 mice were randomly divided into a sham operation group, a model group and an EA group, 10 mice in each one. The model of MI was established in the model group and EA group by ligating the left anterior descending branch of coronary artery. The mice in the sham operation group were not treated with ligating at left anterior descending branch of coronary artery, but the remaining procedure was similar with the model group. The mice in the EA group were treated with EA at "Neiguan" (PC 6) with 2 Hz/100 Hz of frequency and 2 mA of intensity, 20 min per treatment, once a day for totally 5 days. No EA was given for model group and sham operation group. The electrocardiogram was recorded and △ST value was calculated to evaluate the model. TTC staining was applied to evaluate the infarct size. Immunohistochemical (IHC) method was applied to evaluate the positive nerve fiber density in myocardial tissue. Western blot method was applied to test the protein expression levels of neuregulin-1 (NRG-1), tyrosine hydroxylase (TH), growth associated protein-43 (GAP-43).@*RESULTS@#The electrocardiogram (lead II) results indicated compared with the sham operation group, the S-T segments in the model group and EA group were increased obviously (both <0.01), indicating the MI model was established successfully. The TTC staining results indicated compared with sham operation group, the infarction size was significantly increased in the model group (<0.01); compared with the model group, the infarction size in the EA group was significantly reduced (<0.01). The IHC results indicated compared with the sham operation group, the positive nerve fiber density in myocardial was increased in the model group (<0.01); compared with the model group, the positive nerve fiber density in myocardial was reduced in the EA group (<0.05). The Western blot results indicated compared with the sham operation group, the expression levels of TH, NRG-1 and GAP-43 were significantly increased in the model group (<0.01); compared with the model group, the expression level of TH and GAP-43 were significantly reduced (<0.01) and that of NRG-1 was increased in the EA group (<0.05).@*CONCLUSION@#EA could increase the expression of NRG-1 and reduce the expression of TH and GAP-43 in myocardial tissues in MI mice, which could suppress sympathetic nerve hyperexcitability after infarction to achieve myocardial protection effect.
Assuntos
Animais , Masculino , Camundongos , Doença da Artéria Coronariana , Eletroacupuntura , Camundongos Endogâmicos C57BL , Isquemia Miocárdica , MiocárdioRESUMO
Neurons in the laterodorsal tegmentum (LDTg) and pedunculopontine tegmental nucleus (PPTg) play important roles in central autonomic circuits of the kidney.In this study,we used a combination of retrograde tracers pseudorabies virus (PRV)-614 and fluorescence immunohistochemistry to characterize the neuroanatomic substrate of PPTg and LDTg innervating the kidney in the mouse.PRV-614-infected neurons were retrogradely labeled in the rostral and middle parts of LDTg,and themiddle and caudal parts of PPTg after tracer injection in the kidney.PRV-614/TPH double-labeled neurons were mainly localized in the rostral of LDTg,whereas PRV-614/TH neurons were scattered within the three parts of LDTg.PRV-614/TPH and PRV-614/TH neurons were located predominantly in the caudal of PPTg (cPPTg).These data provided direct neuroanatomical foundation for the identification of serotonergic and catecholaminergic projections from the mid-brain tegmentum to the kidney.
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Objective To explore the differences of cultivation and differentiation between cortical neural stem cells(C-NSCs) and mesencephalic neural stem cells(M-NSCs). Methods We dissociated embryonic cortex and ventral mesencephalon respectively,and single cell suspensions were achieved by trypsin digestion and mechanical dissociation in sterile condition.These cells were planted into DMEM/F12 culture medium with B27,bFCF,and then were passaged by mechanical methods and induced to differentiation in DMEM/F12 medium with 10%FBS(without growth factors).For examining the features of C-NSCs and M-NSCs,reverse phasecontrast microscopy,immunocytochemical techniques were applied to detect nestin,NSE,GFAP antigens and the specific antigen(TH) of neurons differentiated from the two kinds of NSCs.We observed and compared the difference of the two kinds of NSCs. Results The NSCs existed both in cortex and ventral mesencephalon of embryonic mice,which expressed nestin and possessed the ability of self-renewing and multipotent, but the density of NSCs in cortex was higher than that in ventral mesencephalon.There were some TH positive cells differentiated from M-NSCs but none came from C-NSCs.Conclusion The proliferative activity of C-NSCs is higher than that of M-NSCs,but more number M-NSCs differentiated into dopaminergic neurons in serum medium.