艾灸对慢性内脏痛敏大鼠脊髓Fos蛋白和sigma-1受体表达的影响

Effects of moxibustion on spinal Fos-expression and sigma-1 receptor in rats with chronic visceral hyperalgesia

目的:观察艾灸对慢性内脏痛敏模型大鼠L6-S1脊髓节段Fos蛋白和sigma-1受体(sigma-1R)表达的影响。方法:采用乳鼠结直肠扩张刺激建立慢性内脏痛敏大鼠模型,雄性SD新生大鼠随机分为正常组、模型组和艾灸组,每组12只。采用腹部撤回反射(AWR)评分检测大鼠内脏痛敏;采用免疫组化的方法观察L6-S1脊髓节段Fos蛋白的表达;Western blot、实时荧光定量PCR检测脊髓节段sigma-1R蛋白及其m RNA的表达。结果:与正常组比较,模型组大鼠AWR评分升高(P<0.01)。艾灸干预后,艾炙组大鼠AWR评分下降(P<0.01,P<0.05)。模型组Fos阳性表达高于正常组(P<0.01),艾灸干预后,艾灸组Fos阳性表达降低(P<0.01)。模型组大鼠sigma-1R蛋白及其m RNA表达均高于正常组(P<0.01),艾灸干预后,艾灸组sigma-1R蛋白及其m RNA表达均降低(P<0.05)。结论:艾灸有效缓解慢性内脏痛敏大鼠的痛敏状态,降低脊髓节段Fos蛋白、sigma-1R蛋白及其m RNA表达。

Objective: To observe the influence of moxibustion on the expression of Fos protein and sigma-1 R(protein and m RNA) in the spinal cord in rats with chronic visceral hyperalgesia(CVH). Methods: CVH rat model induced by mechanical colorectal distention, male SD newborn rats were randomly divided into a normal group, a model group and a moxibustion group, 12 in each one. The abdominal withdrawal reflex(AWR) scores were assessed after moxibustion treatment. The expression of Fos protein in the L6-S1 segments of spinal cord was detected by immunohistochemistry. Protein and m RNA expressions of sigma-1 R in the L6-S1 segments of spinal cord were tested by Western blot and real-time PCR, respectively. Results: Compared with the normal group, the AWR score was increased in the model group(P<0.01). Moxibustion markedly attenuated the AWR scores(P<0.01, P<0.05). The expression of Fos protein in the model group was higher than that in the normal group(P<0.01), and after the intervention, the expression was decreased(P<0.01). The protein and m RNA expressions of sigma-1 R in the spinal cord were significantly increased in the model rats than that in the normal group(P<0.01). Moxibustion increased the expression of sigma-1 R(protein and m RNA) in the model rats(P<0.05). Conclusion: Moxibustion treatment might attenuate CRD-induced CVH in rats and this effect may be due to the moxibustion reduction of Fos and sigma-1 R in the spinal cord.