Jarvik L F, Simpson J H, Guthrie D, Liston E H
Psychopharmacology (Berl). 1981;75(2):124-31. doi: 10.1007/BF00432173.
This study examines the effects of morphine (10 mg/70 kg body weight) versus placebo (isotonic saline) on experimentally induced cold pressor pain threshold and tolerance, on self-reports of psychological states and drug effects, observer ratings of psychological states, and performance on timed cognitive-motor tasks in 20 non-drug using, normal male volunteers (21-28 years of age). Morphine increased both threshold and tolerance for cold pressor pain, and also increased "euphoric" and decreased "clear thinking" responses on the respective scales. Morphine, in contrast to placebo, increased scores on depression, fatigue, and cognitive loss-dysfunction scales and decreased scores on carefree and "friendliness" scales. Three sets of psychological variables were observed to covary significantly: Measures of anxiety and hostility; reports of fatigue and cognitive dysfunction; and reports of carefree feelings and perceptions of clear thinking. While measures of hostility, fatigue, and cognitive dysfunction covaried positively, reports of carefree feelings and perception of clear thinking covaried negatively with increased pain threshold and tolerance. Anxiety, contrary to reports in the literature, also covaried positively with the pain measures. The results were interpreted as supporting a relationship between increased arousal of the nervous system and decreased pain sensitivity in conjunction with the known analgesic effects of morphine.
本研究考察了吗啡（10毫克/70千克体重）与安慰剂（等渗盐水）对20名不使用药物的正常男性志愿者（21 - 28岁）实验性诱发的冷压疼痛阈值和耐受性、心理状态自我报告及药物效果、心理状态的观察者评分以及定时认知运动任务表现的影响。吗啡提高了冷压疼痛的阈值和耐受性，同时在相应量表上增加了“欣快感”反应并降低了“思维清晰”反应。与安慰剂相比，吗啡提高了抑郁、疲劳和认知丧失 - 功能障碍量表的得分，降低了无忧无虑和“友善”量表的得分。观察到三组心理变量显著共变：焦虑和敌意的测量指标；疲劳和认知功能障碍的报告；无忧无虑的感觉和思维清晰感知的报告。虽然敌意、疲劳和认知功能障碍的测量指标呈正共变，但无忧无虑的感觉报告和思维清晰感知与疼痛阈值和耐受性增加呈负共变。与文献报道相反，焦虑也与疼痛测量指标呈正共变。结果被解释为支持神经系统兴奋增加与疼痛敏感性降低之间的关系，以及吗啡已知的镇痛作用。
