不同针法对佐剂性关节炎大鼠下丘脑镇痛效应比较

Comparison of Hypothalamic Analgetic Effects of Different Acupunctures in Adjuvant Arthritis Rats

目的 对电针、毫针、刺血和穴位注射的镇痛效应及下丘脑镇痛机制进行比较研究。方法 以佐剂性关节炎大鼠为炎症痛模型,以“昆仑”为穴位,采用电针、毫针、刺血、穴位注射,以放免、原位杂交等为检测方法,观察了痛阈、炎症局部肿胀度、下丘脑β- 内啡肽(β- EP)和促肾上腺皮质激素(ACTH)含量、下丘脑前阿黑皮素(POMC)mRNA表达等指标。结果 4种针法均可使痛阈升高,尤以电针、穴注升高明显;均可使炎症局部肿胀减轻,各组间疗效无明显差异;电针、毫针可提高下丘脑βEP含量,以电针作用最强;穴注可提高下丘脑ACTH含量;电针、毫针可增强下丘脑POMCmRNA表达。结论 电针、毫针、刺血、穴注对炎症痛均有镇痛作用,以电针、穴注疗效较好。在下丘脑水平,电针、毫针可能通过提高下丘脑β- EP含量、增强下丘脑POMCmRNA表达达到镇痛作用;穴注可能通过提高下丘脑ACTH含量达到镇痛作用。刺血可能通过下丘脑β- EP、ACTH以外的途径实现其镇痛效应。

Objective To compare the analgetic effects and hypothalamic analgetic mechanisms of electroacupuncture, filiform-needle acupuncture, blood-letting puncture and point injection.Methods Adjuvant arthritis rat was used as a model of inflammatory pain. Electroacupuncture, filiform-needle acupuncture, blood-letting puncture and point injection were performed at point Kunlun. Pain threshold and the extent of inflammatory focus swelling were examined and hypothalamic β-endorphin (β-EP), adrenocorticotrophic hormone (ACTH) and pre-opium-melanocortin (POMC) mRNA expression were measured by radioimmunoassay and in situ hybridization.Results All four acupuncture methods could raise pain threshold, especially electroacupuncture and point injection, and reduce inflammatory focus swelling without a significant difference among the groups. Electroacupuncture and filiform-needle acupuncture could increase hypothalamic β-EP content with electroacupuncture to a larger extent. Point injection could heighten hypothalamic ACTH content. Electroacupuncture and filiform-needle acupuncture could increase hypothalamic POMCmRNA expression.Conclusion Electroacupuncture, filiform-needle acupuncture, blood-letting puncture and point injection all have a relieving effect on inflammatory pain with electroacupuncture and point injection better. At hypothalamic level, electroacupuncture and filiform-needle acupuncture may produce an analgetic effect through increasing hypothalamic β-EP content and POMCmRNA expression and point injection, through raising hypothalamic ACTH content. Blood-letting puncture may produce an analgetic effect by a way out of hypothalamic β-EP and ACTH.