Effects of transcranial and trans-spinal low frequency magnetic stimulation on the expression of growth associated protein-43 after spinal cord injury
10.3760/cma.j.issn.0254-1424.2012.08.002
- VernacularTitle:经颅和经脊髓低频磁刺激对脊髓损伤后生长相关蛋白-43表达的影响
- Author:
Qiu WANG
;
Tao XU
- Publication Type:Journal Article
- Keywords:
Spinal cord injury;
Magnetic stimulation;
Growth associated protein-43
- From:
Chinese Journal of Physical Medicine and Rehabilitation
2012;34(8):565-569
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the effects of transcranial and trans-spinal low frequency magnetic stimulation (MS) on the expression of growth-associated protein-43 (GAP-43) in the spinal neurons of rats after spinal cord injury (SCI). Methods Forty-five Sprague-Dawley female rats were divided randomly into a transcranial magnetic stimulation (TMS) group,a trans-spinal cord magnetic stimulation group and a model control group with 15 in each group.Another 6 rats served as a normal control group.Spinal cord injury at the T9-10 level was modeled according to the modified Allen's method.The rats in the two MS groups received magnetic stimulation at 0.5 Hz and 75％ of the maximum output intensity ( 1.9 T) of the magnetic stimulator beginning 24 h post injury.They received 30 pulses daily for 28 days while the rats in the model control group were not exposed to MS.Basso-Beattie-Bresnahan (BBB) scale scores and motion evoked potentials (MEPs) were measured at the 1st,7th,14th,21 st and 28th day post injury.The expression of GAP-43 protein was studied using immunohistochemical methods and semi-quantified by Western blotting. Results At the 4th week post injury the average BBB scores in the model control group,the TMS group and the trans-spinal cord magnetic stimulation group were all significantly different. MEP amplitudes decreased significantly in all groups after the injury,and the latency was prolonged,but there were no significant differences among groups at any time point.GAP-43 expression also increased after SCI,and it was significantly higher in the MS groups than in the model control group at 4 weeks. Moreover,the expression of GAP-43 in the trans-spinal cord MS group was significantly greater than in the TMS group.Conclusion Magnetic stimulation can promote nerve regeneration and improve locomotor recovery after spinal cord injury,at least in rats.The effect of trans-spinal cord magnetic stimulation is superior to that of TMS.The mechanism may be related to the activation of central pattern generators.
