A Preliminary Study On The Effects Of Acupuncture On Nerve Growth Factor In Spinal Cord And Spared Dorsal Root Ganglion

Objective: To explore the expression changes of nerve growth factor(NGF)of spinal cord and spared dorsal root ganglion(DRG) following partial dorsal rhizotomy and acupuncture in animals so as to unveil the relation between NGF and Acupuncture Promote the plasticity of spinal cord.Methods : Twenty adult cats and twenty rats were respectively divided into 4 groups:normal control group;a cup spared DRG for 3 days,7 days and 14 days group,in which bilateral L1-L5,L7-S2DRG were removed,and L6DRG were spared in cats;but bilateral L1-L4,L6- S2DRG were removed,and L5DRG were spared in rats;then unilaterally two sets of acupoints〔Zusanlily and Xuanzhong;Futu and Sanyinjiao located in the distribution area of spinal nerve L5,L6〕were electro-stimulated alternatively 30mins everyday by electro-needling. Five animals were used in every group. After that, samples were extracted from the animals at the 3rd,the 7th and the 14th day respectively after the operation. Later, SABC immunohistochemistry and Western-blot techniques were applied to detect the protein expression changes of NGF in spinal cord and spared DRG,and Image analysis system and Gel imagery system to calculate the IOD of the positive results.Results: 1.(1) Protein expression of NGF in spinal lamina II, Clarke's nucleus and DRG were detected. The positive neurons were stained in kytoplasm, nucleus,but the stains were opacus in nucleus; (2) The acupuncture side of the 7th, the 14th day group,the IOD of the protein expression of NGF in spared DRG were elevated apparently as compared with that of the non-acupuncture side(P<0.05); moreover, the acupuncture side of the 3rd,7th,14th day group and the IOD of the protein expression of NGF increased obviously in turn as time went on,and two sides of the 7th,14th day group together with the IOD of the protein expression of NGF in spared DRG were elevated apparently as compared with that of the normal control group (P<0.05); (3) The acupuncture side of spinal lamina II,Clarke's nucleus, the IOD of the protein expression of NGF were elevated apparently as compared with that of the non-acupuncture side and normal control group (P<0.05). Nevertheless there was no significant difference between the acupuncture side and non- acupuncture side in terms of interclass (P>0.05). 2.(1) The protein expression of NGF in spinal cord and spared DRG of cats were detected. The protein expression of NGF in the Bilateral spared DRG of the 7th,4th day group increased apparently as compared with that of the normal control group (P<0.05). Nevertheless, there was no significant difference between the 3rd day group and the normal control group (P>0.05); (2) In spinal dorsal horn, the protein expression of NGF was found of no significant difference in the Bilateral spinal dorsal horn of each group or interclass (P>0.05).Conclusion1.There is protein expression of NGF in the spinal cord and spared DRG.2.Acupuncture has not affected the protein expression of NGF in the spinal cord.3.Acupuncture is able to promote the up-regulation of the protein expression of NGF in the spared DRG, and in 14 days,the tendency is reinforced as time passed. It indicates that NGF is perhaps related to the spinal plasticity.