Guo Min, Chen Su, Liu Xiangming
Department of Biological & Medical Engineering, South-Central University for Nationalities, Wuhan, 430074, China.
Sci China C Life Sci. 2008 Nov;51(11):1025-38. doi: 10.1007/s11427-008-0133-6. Epub 2008 Nov 7.
In vivo experiments were designed to verify the analgesic effect of Dragon's Blood and the material basis for this effect. Extracellular microelectrode recordings were used to observe the effects of Dragon's Blood and various combinations of the three components (cochinchinenin A, cochinchinenin B, and loureirin B) extracted from Dragon's Blood on the discharge activities of wide dynamic range (WDR) neurons in spinal dorsal horn (SDH) of intact male Wistar rats evoked by electric stimulation at sciatic nerve. When the Hill's coefficients describing the dose-response relations of drugs were different, based on the concept of dose equivalence, the equations of additivity surfaces which can be applied to assess the interaction between three drugs were derived. Adopting the equations and Tallarida's isobole equations used to assess the interaction between two drugs with dissimilar dose-response relations, the effects produced by various combinations of the three components in modulating the evoked discharge activities of WDR neurons were evaluated. Results showed that Dragon's Blood and its three components could inhibit the evoked discharge frequencies of WDR neurons in a concentration-dependent way. The Hill's coefficients describing dose-response relations of three components were different. Only the combined effect of cochinchinenin A, cochinchinenin B and loureirin B was similar to that of Dragons Blood. Furthermore, the combined effect was synergistic. This investigation demonstrated that through the synergistic interaction of the three components Dragon's Blood could interfere with the transmission and processing of pain signals in spinal dorsal horn. All these further proved that the combination of cochinchinenin A, cochinchinenin B, and loureirin B was the material basis for the analgesic effect of Dragon's Blood.
设计体内实验以验证血竭的镇痛作用及其作用的物质基础。采用细胞外微电极记录技术，观察血竭及其提取的三种成分（柯嗪 A、柯嗪 B 和龙血素 B）的不同组合对完整雄性 Wistar 大鼠坐骨神经电刺激诱发的脊髓背角（SDH）广动力范围（WDR）神经元放电活动的影响。当描述药物剂量 - 反应关系的 Hill 系数不同时，基于剂量等效性的概念，推导了可用于评估三种药物之间相互作用的加和表面方程。采用这些方程以及 Tallarida 用于评估具有不同剂量 - 反应关系的两种药物之间相互作用的等效线方程，评估了三种成分的不同组合对 WDR 神经元诱发放电活动的调节作用。结果表明，血竭及其三种成分均可浓度依赖性地抑制 WDR 神经元的诱发放电频率。描述三种成分剂量 - 反应关系的 Hill 系数不同。只有柯嗪 A、柯嗪 B 和龙血素 B 的联合作用与血竭相似。此外，联合作用具有协同性。本研究表明，血竭可通过三种成分的协同相互作用干扰脊髓背角疼痛信号的传递和处理。所有这些进一步证明，柯嗪 A、柯嗪 B 和龙血素 B 的组合是血竭镇痛作用的物质基础。
