Morgan M M, Depaulis A, Liebeskind J C
Department of Psychology, University of California, Los Angeles 90024.
Brain Res. 1987 Oct 13;423(1-2):395-8. doi: 10.1016/0006-8993(87)90870-5.
Electrical stimulation of the periaqueductal gray matter (PAG) of the rat can produce both analgesia and aversive reactions. To determine if these two effects can be dissociated, diazepam, a benzodiazepine, was administered to rats chronically implanted with electrodes in the PAG. The threshold for stimulation-produced analgesia or aversion, whichever was lowest, was determined before and after drug administration. Diazepam (1 mg/kg) attenuated stimulation-produced aversive reactions at 12 of 20 stimulation sites, allowing analgesia to be measured at the same threshold. Diazepam did not alter baseline pain sensitivity or thresholds for stimulation-produced analgesia. These results indicate that aversive reactions and analgesia from PAG stimulation can be pharmacologically dissociated.
对大鼠中脑导水管周围灰质（PAG）进行电刺激可产生镇痛和厌恶反应。为了确定这两种效应是否可以分离，将苯二氮䓬类药物地西泮给予长期在PAG植入电极的大鼠。在给药前后分别测定刺激产生的镇痛或厌恶反应的阈值，取二者中的较低值。地西泮（1毫克/千克）在20个刺激位点中的12个位点减弱了刺激产生的厌恶反应，从而能够在相同阈值下测量镇痛效果。地西泮未改变基线疼痛敏感性或刺激产生镇痛的阈值。这些结果表明，PAG刺激产生的厌恶反应和镇痛作用可以通过药理学方法分离。
