Richter J A, Goldstein A
Proc Natl Acad Sci U S A. 1970 Jul;66(3):944-51. doi: 10.1073/pnas.66.3.944.
Mice were made tolerant to a large dose of levorphanol, a congener of morphine. Then (3)H-levorphanol was given. The concentration of free, unchanged levorphanol in the brain water (ultrafiltrate) was found to be much higher than required to produce pharmacologic effects in nontolerant animals. The result indicates that tolerance arises from a diminished sensitivity to the drug at cellular or subcellular sites of drug action in the brain.
将小鼠制成对大剂量左啡诺(吗啡的同类物)耐受。然后给予³H-左啡诺。发现脑水(超滤液)中游离、未变化的左啡诺浓度远高于在未耐受动物中产生药理作用所需的浓度。结果表明耐受性源于大脑中药物作用的细胞或亚细胞部位对药物的敏感性降低。