Effect of Acupotomy Lysis at Cervical Acupoints on Expression of Matrix Metalloproteinases and Tissue Inhibitor of Metalloproteinase 1 and Changes of Pulpiform Nucleus Ultrastructure in Rats with Degenerated Cervical Intervertebral Discs

To observe the effect of acupotomy lysis at acupoints around the neck on expression of matrix metalloproteinase 1 (MMP-1), MMP-2 and tissue inhibitor of metalloproteinase 1 (TIMP-1) genes and ultrastructure of pulpiform nucleus in cervical intervertebral disc degeneration (IVDD) rats, so as to explore its mechanism underlying easing IVDD.SD rats were randomly allocated to control (n = 15), model (n = 14), Jiaji (EX-B 2, n = 13), cervico-acupoint (n = 14) and medication groups (n = 14). The cervical IVDD model was established by using static-dynamic imbalance method. For rats of the Jiaji (EX-B 2) and cervico-acupoint groups, EX-B 2-points of the cervical 2-7 segments, and peri-cervical acupoints: bilateral "Naokong" (GB 19) , "Naohu" (GV 17), "Dazhui" (GV 14), bilateral "Quyuan" (SI 13) and bilateral "Tianzong" (SI 11) were separately punctured with a needle-knife, once every 5 days for 3 times, and for rats of the medication group, Brufen Capsules (15 mg · kg(-1) · d(-1)) and Jingfukang Granule (0.5 mg · kg(-1) · d(-1)) were given by intragastric administration, once daily for 10 days. The expression levels of MMP-1, MMP-3 and TIMP-1 genes in the pulpiform nucleus of cervical intervertebral discs were detected by RT-PCR and changes of the ultrastructure of the pulpiform nucleus observed under transmission electron microscope.Compared to the control group, the expression levels of MMP-1 mRNA and MMP-3 mRNA of the cervical intervertebral disc tissues were significantly up-regulated in the model group (P 0.05). No significant differences were found between the Jiaji (EX-B 2) and cervico-acupoint groups in down-regulating MMP-1 mRNA and MMP-3 mRNA expression and up-regulating TIMP-1 mRNA expression (P > 0.05). Results of electron microscope examinations showed that the ultrastructural injury changes of cells of the pulpiform nucleus were relatively milder in the Jiaji (EX-B 2) and cervico-acupoint groups, followed by the medication group in comparison with those of the model group.Acupotomy lysis at acupoints around the neck can improve the ultrastructural changes of cells of the pulpiform nucleus of cervical intervertebral discs in IVDD rats, which is possibly by regulating the expression of MMP-1, MMP-3 and TIMP-1 genes.