Paterson N E, Myers C, Markou A
Department of Neuropharmacology, The Scripps Research Institute, La Jolla, CA 92037, USA.
Psychopharmacology (Berl). 2000 Nov;152(4):440-6. doi: 10.1007/s002130000559.
The study of the effects of repeated amphetamine administration and withdrawal on brain reward function has relevance to both amphetamine dependence and non-drug-induced depressions.
The purpose of this study was to investigate the effects of continuous amphetamine administration and withdrawal on brain stimulation reward thresholds, and the changes that occur with repeated amphetamine exposures.
Rats were prepared with bipolar electrodes in the lateral hypothalamus and trained in a discrete-trial reward threshold procedure. Then, rats underwent two separate periods of amphetamine administration via subcutaneous osmotic mini-pumps.
Continuous amphetamine administration was associated with lowering in brain reward thresholds and decreases in response latencies, while withdrawal was associated with threshold elevations. These effects changed with subsequent amphetamine administration and withdrawal.
The results of this study indicated that with the amphetamine administration regime used here, rats developed increased sensitivity to the effects of acute amphetamine administration and tolerance to the effects of amphetamine withdrawal.
研究反复给予苯丙胺及其戒断对大脑奖赏功能的影响，对于理解苯丙胺依赖和非药物诱导的抑郁症均具有重要意义。
本研究旨在探究持续给予苯丙胺及其戒断对脑刺激奖赏阈值的影响，以及反复接触苯丙胺后所发生的变化。
将大鼠双侧下丘脑植入双极电极，并通过离散试验奖赏阈值程序进行训练。然后，大鼠通过皮下渗透微型泵接受两个不同阶段的苯丙胺给药。
持续给予苯丙胺会导致脑奖赏阈值降低和反应潜伏期缩短，而戒断则与阈值升高有关。这些效应会随着后续苯丙胺给药和戒断而发生变化。
本研究结果表明，采用此处所用的苯丙胺给药方案，大鼠对急性给予苯丙胺的效应变得更加敏感，而对苯丙胺戒断的效应产生了耐受性。
