Larson A A, Vaught J L, Takemori A E
Eur J Pharmacol. 1980 Feb;61(4):381-3. doi: 10.1016/0014-2999(80)90077-1.
In two strains of rats, intrathecal administration of morphine and met-enkephalin was found to produce a dose-dependent analgesic effect as measured by the tail-flick assay. Prior administration of leu-enkelphalin at a dose which had no analgesic effect was found to reduce significantly the analgesic ED50 of both morphine and met-enkephalin. Met-enkephalin pretreatment, at a similar sub-analgesic dose, was without effect. Thus, a differential interaction of the enkephalins with morphine is evident at spinal structures.
在两种品系的大鼠中，通过甩尾试验发现鞘内注射吗啡和甲硫氨酸脑啡肽可产生剂量依赖性镇痛作用。预先给予无镇痛作用剂量的亮氨酸脑啡肽可显著降低吗啡和甲硫氨酸脑啡肽的镇痛半数有效剂量（ED50）。以类似的亚镇痛剂量进行甲硫氨酸脑啡肽预处理则无此效果。因此，脑啡肽与吗啡在脊髓结构上存在明显的差异相互作用。
