Objective: To observe the effect of acupotome relaxing at cervical acupoints on type I and II collagens of degenerated cervical intervertebral discs in rats, so as to explore its potential mechanism underlying anti-degeneration of intervertebral discs.
Methods: Rats were randomly divided into control, model, Jiaji acupoints, cervical acupoints and medication groups (n = 15 in each group). The rat model of cervical intervertebral disc degeneration due to static-dynamic imbalance was made as previously specified. The Jiaji acupoints were those located along the cervical vertebra 2-7. The cervical acupoints included bilateral "Naokong"(GB 19) , "Naohu" (GV 17) , "Dazhui"(GV 14) , bilateral "Quyuan" (SI 13) and bilateral "Tianzong" (SI 11). Acupoints were treated according to the procedures of acupotome for 3 times in ten days with five days' break between every two treatment sessions. Rats of the medication group were intragastrically administered with Jing Fu Kang Granules and ibuprofen daily for ten days. Twenty days after the end of treatment, all rats were sacrificed for further examination of morphological changes of the intervertebral disc tissue. Immunoactivity of protein and mRNA expression levels of collagen type I and II of the intervertebral discs were measured by means of immunohistochemistry and RT-PCR, respectively.
Results: In comparison with the control group, the immunoactivity and mRNA expression levels of collagen type I and II of the intervertebral discs were significantly elevated or reduced in rats of the model group, respectively (P < 0.05). After acupotome intervention and medication, the increased and decreased expression levels of type I and II collagen proteins and genes were markedly reversed (P < 0.05). The effects of acupotome relaxing of both cervical and Jiaji acupoints were significantly superior to those of medication in down-regulating expression of type I collagen protein and mRNA, and in up-regulating that of type II collagen protein and mRNA (P < 0.05). No significant differences were found between the cervical acupoints and Jiaji acupoints groups in the above- mentioned outcomes (P > 0.05) . The degree of severity of the degenerated intervertebral discs was the worst in the model group, followed by the medication group, then the Jiaji acupoints group and cervical acupoints group, and the control group the least.
Conclusion: Acupotome at neck acupoints can regulate the extracellular matrix of the intervertebral disc via inhibiting the transformation between type I and type II collagens, which may contribute to its effect in delaying the degenerative process of the cervical intervertebral discs.