Benyhe S, Varga E, Borsodi A, Wollemann M
Institute of Biochemistry, Hungarian Academy of Sciences, Szeged.
Acta Physiol Hung. 1990;76(4):291-4.
Opioid receptors of the frog (Rana esculenta) brain are characterized mainly by their relatively high ethylketocyclazocine (EKC) binding properties and by their low affinity to mu and delta ligands when D-Ala2-(Me)Phe4-Gly5-ol enkephalin (DAGO) and D-Ala2-Leu5-enkephalin (DALE) is used. In competition experiments it has been established that EKC and N-cyclopropylmethyl-norazidomorphine (CAM), which are non-selective kappa-ligands, have relatively high affinity to frog brain as well as the kappa 2 (which is DALE sensitive subpopulation of the kappa receptor) ligands etorphine and Metenkephalin-Arg6-Phe7 (1.). The kappa 2 subtype in frog brain resembles more to the mu subtype than to the delta subtype of opioid receptors, but it differs from the mu subtype in displaying low affinity toward beta-endorphin and DAGO.
青蛙（食用蛙）大脑中的阿片受体主要特征在于，当使用D - 丙氨酸2 - （甲基）苯丙氨酸4 - 甘氨酸5 - 脑啡肽（DAGO）和D - 丙氨酸2 - 亮氨酸5 - 脑啡肽（DALE）时，它们具有相对较高的乙基酮环唑新（EKC）结合特性，以及对μ和δ配体的低亲和力。在竞争实验中已经确定，作为非选择性κ配体的EKC和N - 环丙基甲基 - 去甲叠氮吗啡（CAM）对青蛙大脑具有相对较高的亲和力，以及κ2（即κ受体的DALE敏感亚群）配体埃托啡和甲硫氨酸脑啡肽 - 精氨酸6 - 苯丙氨酸7（1.）。青蛙大脑中的κ2亚型与阿片受体的μ亚型相比，更类似于δ亚型，但它与μ亚型的不同之处在于对β - 内啡肽和DAGO显示出低亲和力。
