Kest B, Jenab S, Brodsky M, Elliott K, Inturrisi C E
Department of Pharmacology, Cornell University Medical College, New York, New York 10021.
J Neurosci Res. 1994 Dec 15;39(6):674-9. doi: 10.1002/jnr.490390608.
Delta opioid receptor (DOR) mRNA levels were studied in mice rendered tolerant to [D-Ala2]deltorphin II by 4 days of repeated intracerebroventricular administration (10 micrograms, [tid]). ED50 determinations on day 5 revealed a 10-fold loss in [D-Ala2]deltorphin II potency with the tail-flick test. Utilization of a microdissection technique followed by quantitative solution hybridization of RNA extracts from mouse brain revealed mean levels of DOR mRNA ranging from 3.9 pg/micrograms RNA in the caudate-putamen to 0.4 pg/micrograms RNA in the cerebellum. DOR mRNA levels were not different when RNA extracts from tolerant and non-tolerant mice were compared. These data suggest that altered DOR mRNA levels are not one of the adaptive changes that occur with delta opioid ([D-Ala2]deltorphin II) tolerance.
通过4天重复脑室内给药（10微克，每日三次）使小鼠对[D - Ala2]强啡肽II产生耐受性，然后研究δ阿片受体（DOR）mRNA水平。第5天的半数有效剂量（ED50）测定显示，甩尾试验中[D - Ala2]强啡肽II的效力损失了10倍。采用显微解剖技术，随后对从小鼠脑提取的RNA进行定量溶液杂交，结果显示DOR mRNA的平均水平范围为：尾状核 - 壳核中为3.9 pg/微克RNA，小脑中为0.4 pg/微克RNA。比较耐受和未耐受小鼠的RNA提取物时，DOR mRNA水平没有差异。这些数据表明，DOR mRNA水平的改变不是δ阿片类药物（[D - Ala2]强啡肽II）耐受性所发生的适应性变化之一。
