Pain Y Z, Wang L H, Tang Y H, Yin X M, Wang S
Department of Physiology, Norman Bethune University of Medical Sciences, Changchun.
Sheng Li Xue Bao. 1992 Aug;44(4):326-32.
.1 mol/L CaCl2 0.5 microliters, 0.06 mol/L ACh 0.5 microliters, 5.4 x 10(-3) mol/L gallamine triethiodide (cholinergic nicotinic receptor blocker) 0.5 microliter and 14.4 x 10(-3) mol/L atropine (cholinergic muscarinic receptor blocker) 0.5 microliter were injected through bilateral intracranial cannulae in rat habenula. Pain threshold was measured by the latency of tail-flick reflex elicited by radiant heat exposure before and after intracerebral injection. CaCl2 significantly reduced the basic pain threshold and weakened the effect of the acupuncture analgesia. ACh apparently antagonized the effect of acupuncture analgesia. Gallamine triethiodide could recover the pain threshold almost to the raised level by acupuncture, but atropine only strengthened the effect on pain threshold weakly and briefly. The results suggest that the antagonistic effect of Ca2+ may be mediated via ACh in habenula.
将0.1摩尔/升氯化钙0.5微升、0.06摩尔/升乙酰胆碱0.5微升、5.4×10⁻³摩尔/升三碘季铵酚（胆碱能烟碱受体阻滞剂）0.5微升和14.4×10⁻³摩尔/升阿托品（胆碱能毒蕈碱受体阻滞剂）0.5微升通过双侧颅内套管注射到大鼠缰核中。在脑内注射前后，通过辐射热暴露诱发的甩尾反射潜伏期来测量痛阈。氯化钙显著降低基础痛阈并减弱针刺镇痛效果。乙酰胆碱明显拮抗针刺镇痛作用。三碘季铵酚几乎可使痛阈恢复到针刺提高后的水平，但阿托品仅对痛阈有微弱且短暂的增强作用。结果表明，Ca²⁺的拮抗作用可能通过缰核中的乙酰胆碱介导。
