Sharp T, Zetterström T, Ljungberg T, Ungerstedt U
Brain Res. 1987 Jan 20;401(2):322-30. doi: 10.1016/0006-8993(87)91416-8.
An intracerebral microdialysis method was used in awake rats to directly compare the effect of amphetamine on dopamine (DA) release in the striatum and nucleus (n.) accumbens with alterations in behaviour. Amphetamine (0.5-5.0 mg/kg, s.c.) caused a dose-dependent release of DA in both brain regions; however the n. accumbens appeared for the most part more sensitive to amphetamine than the striatum. At each individual dose of the drug, 0.5, 2.0 and 5.0 mg/kg s.c., DA release was closely followed over the time course by the overall behavioural syndrome. Certain components of behaviour showed a regional-specific association with DA release. The intensity of stereotyped head and forepaw movements was closely correlated over the dose range with the amount of DA released in striatum but not n. accumbens. Over the time course, however, the occurrence of this behaviour was delayed compared to increased striatal DA release. In contrast, increased locomotor activity was correlated with the time course change in, and amount of, DA released in n. accumbens by low doses of amphetamine, but not at any dose with DA released in striatum. Repetitive sniffing was better correlated with DA released in n. accumbens than striatum. These in vivo measurements of DA release add further support to the hypothesis that amphetamine-induced stereotypy and locomotion are mediated via DA released in striatum and n. accumbens, respectively. Our data suggest that the occurrence of intense stereotypy rather than locomotor activity at high doses of amphetamine is not due to a selection action in striatum but probably competition between the two behaviours.(ABSTRACT TRUNCATED AT 250 WORDS)
在清醒大鼠中采用脑内微透析法，直接比较苯丙胺对纹状体和伏隔核中多巴胺（DA）释放的影响以及行为变化。苯丙胺（0.5 - 5.0 mg/kg，皮下注射）在两个脑区均引起剂量依赖性的DA释放；然而，伏隔核在很大程度上似乎比纹状体对苯丙胺更敏感。在药物的每个单独剂量（0.5、2.0和5.0 mg/kg皮下注射）下，随着时间推移，DA释放与整体行为综合征密切相关。行为的某些成分显示出与DA释放的区域特异性关联。刻板的头部和前爪运动强度在剂量范围内与纹状体中释放的DA量密切相关，但与伏隔核中释放的DA量无关。然而，随着时间推移，这种行为的出现与纹状体DA释放增加相比有所延迟。相比之下，低剂量苯丙胺引起的运动活动增加与伏隔核中DA释放的时间进程变化和释放量相关，但与纹状体中释放的DA在任何剂量下均无关。重复性嗅探与伏隔核中释放的DA相关性比纹状体中更强。这些DA释放的体内测量结果进一步支持了以下假设：苯丙胺诱导的刻板行为和运动分别通过纹状体和伏隔核中释放的DA介导。我们的数据表明，高剂量苯丙胺时强烈刻板行为而非运动活动的出现并非由于纹状体中的选择作用，而可能是这两种行为之间的竞争。（摘要截断于250字）
