大鼠伏核微量注入加压素及抗加压素血清对痛阈及电针镇痛的影响

The Effects of Microinjection of Arginine－Vasopressin orAnti－Vasopressin Serum into Nucleus Accumbens on Pain Threshold and Electroacupuncture Analgesia in Rats

用56只Wistar大鼠，以辐射热甩尾法的甩尾潜伏期作为痛阈，观察伏核微量注入精氨酸加压素（AVP）或抗AVP血清（AAVPS）对痛阈及电针镇痛的影响。伏核内微量注入AVP（0.015单位）既可提高痛阈又可增强电针镇痛效应，1、2和3伏电针的平均针效与对照组比增加了33％（P＜0．01），停针后且有40min的后效。AAVPS（1μl）注入伏核消除了内源性AVP的作用后，痛阈明显降低且减弱了电针镇痛作用，1伏的针效与对照组比较减弱了15％、2、3V的针效削弱了32％（P＜0.01）。结果提示：脑内内源性的AVP可通过伏核途径调制痛敏感性和电针镇痛效应。

56 Wistar rats were used in this experiment.The tail-flick latency of radiant heat tail－flick test was taken as the index for pain threshold(PT).The effects of microinjection of Arginine vasopressin(AVP) or anti-AVP serum(AAVPS) into the nucleus accumbens(NA) on the PT and electroacupuncture analgesia(EAA) were observed.Microinjection of AVP(0.015U) into the NA could either raise the PT or enhance the electroacupuncture(EA) effect.The mean analgesic effect of 3 steps(1-2-3 V) during EA was increased by 33％(P＜0.01).as compared with the control group,but the after-effect could last 40 minutes after the cessation of EA.However,after the endogenous AVP action was abolished by microlnjection of AAVPS(1μ1),the PT was remakably reduced,and EAA action was also weakened.Analgesic effect of 1V was lowered by 15％ and 2V or 3V by 32％(P＜0.01),as compared with the control group.The results suggest that endogenous AVP in the brain might modulate pain sensitivity and EAA effect through the way of NA．