Zhen Ci Yan Jiu. 1989 ; 14(4): 452-62.

[The change of the concentration of substance P in the rats "channel" "point" skin and plasma in the acupuncture analgesia]

Cao LQ, Wang T.

Numerous reports indicated that substance p (SP) was a neurotransmitter involved in nociception, it also had analgesic effects in the most part of the central nervous system of all mammals, including man. The numbers of mast cell in human's some acupoint tissue were much higher than the non-acupoint tissue, there was connection between the nerves and mast cells which contained SP particles. Therefore, it is worth studying the change of the concentration of SP in the skin and plasma of rats during the process of acupuncture analgesia. 55 rats were divided into 8 groups; (1) Control group; (2) Heat stimulation group; (3) Electro-acupuncture group; (4) Morphine group; (5) Naloxone (NX) group; (6) NX plus electro-acupuncture group; (7) Non-acupoint electro-acupuncture group; (8) Normal saline solution group. The concentration of SP in the "channel" "acupoint" skin and plasma of rats were determined by radioimmunoassay (RIA). The results show that after acupuncture, the tail-flick threshold is increased, the concentration of SP in the skin and plasma is decreased significantly and the effect of electro-acupuncture is abolished by naloxone (i.p). The results suggest that SP is a transmitter relating to skin nociception and involves the process of pain regulation. Electro-acupuncture can inhibit SP release from the skin and the plasma of rats. There is a functional interaction between SP and endorphin in the effects of electro-acupuncture. That is the SP decreased induced by electro-acupuncture may depend upon the function of opiate receptors.