自从1975年 Hughes 等发现甲啡肽和亮啡肽以来

许多研究工作已表明

EK 与针刺镇痛关系密切。应用放射免疫(RIA)法的研究表明

大鼠电针后尾核和下丘脑的EK 含量升高

并与针效呈正相关;用抑制 EK 降解的肽酶抑制剂给大鼠腹腔注射(ip)和家兔测脑室注射后

可使针刺镇痛效应提高

同时大鼠尾核和下丘脑 EK 含量升高。Vacca 等曾应用 PAP 法研究了In the present paper

the relationship between the enkephalin-like immuno- reactivity (EK-LIR) and the electroacupuncture (EA) analgesia was studied by immunohistochemical techniques in guinea pig's adrenal and spinal cord.I.In accordance with the pairing design of experiment

56 male guinea pigs were divided into 28 pairs.Each pair was randomly divided into the test group with EA and the control group without EA.2.In accordance with the ran- domized blocks design of experiment

18 male guinea pigs were divided into 6 blocks.Each block was randomly divided into 3 groups:1.naloxone plus EA group;2.EA group;3.control group without EA.The acupoints were bi- lateral“Zusanli”.The results showed as follows: 1.In the test group

the pain threshold after EA increased from 0.26 ±0.02 mA to 0.47±0.05mA (P<0.001);In the adrenal medulla and spinal cord

both the met-enkephalin (MEK)-LIR and leu-enkephalin (LEK)-LIR in the test group were much weaker than that in the control group (P<0.01); Correlation analysis between the effect of EA analgesia and the MEK-LIR or LEK-LIR in the adrenal medulla and spinal cord respectively revealed that there was a significant negative correlation only between the LEK-LIR and the effect of EA analgesia (P<0.05). 2.After naloxone injection followed by EA

the pain threshold did't increase.But it increased obviously after saline injection followed by EA (P<0.01);In the adrenal medulla

the MEK-LIR and LEK-LIR in the naloxone plus EA group and the EA group were about the same

but much weaker than that in the control group withou(?) EA (P<0.01).In the spinal cord

the two kinds of EK-LIR in the naloxone plus EA group and the control group without EA were much the same

but much greater than that in the EA group (P< 0.01).