禁食大鼠中吗啡未能增加纹状体3,4-二羟基苯乙酸水平。

Failure of morphine to increase striatal 3,4-dihydroxyphenylacetic acid in fasted rats.

作者信息

De Montis G M, Olianas M C, Di Lorenzo C, Tagliamonte A

出版信息

Eur J Pharmacol. 1978 Jan 1;47(1):121-3. doi: 10.1016/0014-2999(78)90382-5.

Abstract

Morphine given to rats fed ad libitum increased the striatal levels of DA and DOPAC while naloxone had no effect. Conversely, after prolonged fasting, morphine failed to increase both DA and DOPAC, while naloxone markedly decreased striatal DOPAC concentration. Intermediate sensitivity to the DOPAC increasing effect of morphine and to the DOPAC decreasing effect of naloxone was present in rats trained to eat their daily meal within 2 h, at different times after feeding. It is concluded that striatal DA synthesis in fasted rats is sustained by an increased endorphin-like activity.

摘要

随意进食的大鼠注射吗啡后，纹状体中多巴胺（DA）和3,4-二羟基苯乙酸（DOPAC）水平升高，而注射纳洛酮则无此作用。相反，长期禁食后，吗啡未能使DA和DOPAC水平升高，而纳洛酮则显著降低纹状体DOPAC浓度。在经过训练在进食后不同时间2小时内吃完每日餐食的大鼠中，观察到对吗啡增加DOPAC的作用和纳洛酮降低DOPAC的作用具有中等敏感性。由此得出结论，禁食大鼠纹状体DA合成是由内啡肽样活性增加所维持的。