LaBella F S, Pinsky C, Dua A
Neuropeptides. 1986 Feb-Mar;7(2):109-12. doi: 10.1016/0143-4179(86)90086-7.
Studies on slices from whole rat brain indicate that the opioid peptide/receptor, but not the opiate drug/receptor, complex is internalized by metabolically-dependent processes. Opiate drugs displace 3H-etorphine from high affinity binding sites with potencies identical to those in brain homogenates. 3H-metenkephalin (ME) binds to a high affinity (IC50 10 nM) and a low affinity (micromolar) site. Opiate drugs and beta-endorphin compete at the high affinity but not at the low affinity binding site for ME. The biological relevance of the low affinity ME-binding site, which like the high affinity site is internalized, remains to be determined. The slice technique should be useful in the characterization of receptor dynamics that may be altered during opiate tolerance and dependence.
对全鼠脑切片的研究表明，阿片肽/受体复合物，而非阿片类药物/受体复合物，是通过代谢依赖过程内化的。阿片类药物从高亲和力结合位点取代³H-埃托啡的效力与在脑匀浆中的效力相同。³H-甲硫脑啡肽（ME）与一个高亲和力（IC50为10 nM）位点和一个低亲和力（微摩尔级）位点结合。阿片类药物和β-内啡肽在ME的高亲和力结合位点竞争，但不在低亲和力结合位点竞争。低亲和力ME结合位点与高亲和力位点一样会被内化，其生物学意义尚待确定。切片技术在表征阿片类药物耐受和依赖过程中可能改变的受体动力学方面应会有用。
