Jacob J
Agents Actions. 1981 Dec;11(6-7):634-6. doi: 10.1007/BF01978772.
The involvement of endogenous morphines (enkephalins and endorphins) in the regulation of pain is demonstrated by the following experimental evidence: (a) their analgesic activities; (b) their distribution in the central nervous systems; (c) the effects of their modifiers, especially of their antagonists, on nociceptive reactions and (or) on various types of analgesia; (d) rare modifications of their brain levels in pain and (or) analgesic states. Besides the well-known facts, the following items are particularly stressed: the functional roles of hypothalamic structures and of the pituitary, the effects of antagonists, the variety of analgesia following noxious and (or) stressful stimuli, genetic and environmental factors, endogenous antinociceptive substances other than opioids, relations with biogenic amines. As a whole, endogenous morphines apparently filter the particular important sensory input represented by nociception and control the reactions to pain, allowing for adjusted behaviour, if the stimuli are avoidable, or for prevention or at least delay of exhaustion if the stimuli are unavoidable.
内源性吗啡（脑啡肽和内啡肽）参与疼痛调节可通过以下实验证据得以证明：（a）它们的镇痛活性；（b）它们在中枢神经系统中的分布；（c）其调节剂，尤其是拮抗剂，对伤害性反应和（或）对各种类型镇痛的影响；（d）在疼痛和（或）镇痛状态下其脑内水平的罕见变化。除了这些众所周知的事实外，还特别强调以下几点：下丘脑结构和垂体的功能作用、拮抗剂的作用、有害和（或）应激刺激后的多种镇痛类型、遗传和环境因素、除阿片类药物外的内源性抗伤害感受物质、与生物胺的关系。总体而言，内源性吗啡显然对由伤害性感受所代表的特别重要的感觉输入进行筛选，并控制对疼痛的反应，若刺激可避免，则允许进行适应性行为，若刺激不可避免，则预防或至少延缓疲劳。
