Childers S R, Creese I, Snowman A M, Synder S H
Eur J Pharmacol. 1979 Apr 1;55(1):11-8. doi: 10.1016/0014-2999(79)90142-0.
The potencies of various opiates in displacing several 3H-opiate ligands' binding to rat membranes vary depending on the nature of the ligand. Whereas opiate antagonists, as well as the opioid peptides and some agonists (etorphine, levorphanol and phenazocine) display similar affinities in displacing either 3H-opiate or 3H-methionine enkephalin binding, other agonists (such as morphine and oxymorphone) are considerably (20-50 times) weaker in displacing 3H-enkephalin than 3H-dihydromorphine binding. These agonists also compete for 3H-enkephalin binding with shallow displacement curves, and are greatly weakened in displacing 3H-naloxone binding in the presence of sodium. These agonists differ from the other opiate classes by possessing a relatively hydrophilic component in their C-ring moieties which may provide a basis for the differential interactions of drugs with the opiate receptor.
各种阿片类药物取代几种3H-阿片类配体与大鼠细胞膜结合的效力因配体的性质而异。阿片类拮抗剂、阿片肽和一些激动剂（埃托啡、左啡诺和非那佐辛）在取代3H-阿片类或3H-甲硫氨酸脑啡肽结合时表现出相似的亲和力，而其他激动剂（如吗啡和羟吗啡酮）在取代3H-脑啡肽结合方面比取代3H-二氢吗啡结合的效力要弱得多（20至50倍）。这些激动剂在取代3H-脑啡肽结合时也具有较浅的位移曲线，并且在有钠存在的情况下，它们取代3H-纳洛酮结合的能力会大大减弱。这些激动剂与其他阿片类药物的不同之处在于，它们的C环部分具有相对亲水的成分，这可能为药物与阿片受体的差异相互作用提供了基础。
