许多研究表明

脑内 P 物质参与针刺镇痛过程;大脑皮层体感Ⅱ区(SⅡ)参与对丘脑中央中核伤害性反应和针刺镇痛效应的下行调节。为了探讨 P 物质是否参与大脑皮层SⅡ区对丘脑的下行调节

本实验观察了电刺激猫 SⅡ区和电针穴位对丘脑中央中核灌流液中 P 物质含量的影响。实验用成年猫

体重1.6～4.1公斤

雌雄不拘。动物随机分为三组:对照组、电针组和 SⅡ区电刺激组

每组分别为10、15和12只。用戊巴比妥钠(40毫克/公斤)麻醉

行开颅术。暴露It was investigated that the effects of electrical stimulation of the somatosensory area Ⅱ(SII)of the cerebral cortex and electroacupuncture on substance P(SP)concentration in the per-fusate from the nucleus centrum medianum(CM)of the thalamus

in order to probe into if SP participates in the SII descending modulation of the nucleus CM and this mechanism of acupunc-ture analgesia.Adult cats were randomly divided into three groups:control

electroacupuncture and electri-cal stimulation of SII.Push-pull perfusion technique was used to collect the perfusate from thenucleus CM.SP contents in the perfusate were determined by radioimmunoassay.The results showed that SP contents in the perfusate have not statistically significantchanges before and after the electrical stimulation of SII or electroacupuncture

suggesting thatthe SP release from the nucleus CM was not influenced by the stimulation of SII or elec-troacupuncture.It is indicated that SP may not associate with the SII descending modulation ofthe nucleus CM and this mechanism of acupuncture analgesia.