Volkow N D, Fowler J S, Wolf A P, Hitzemann R, Dewey S, Bendriem B, Alpert R, Hoff A
Medical Department Brookhaven National Laboratory, Upton, NY 11973.
Am J Psychiatry. 1991 May;148(5):621-6. doi: 10.1176/ajp.148.5.621.
The authors investigated changes in brain function associated with cocaine dependence and withdrawal to provide clues regarding the processes that lead to the uncontrollable self-administration of cocaine.
They measured regional brain metabolism with [18F]-fluorodeoxyglucose (FDG) and positron emission tomography in 15 outpatients with the diagnosis of cocaine abuse and 17 normal comparison subjects. Ten of the patients were studied less than 1 week after they had last had cocaine, and five were studied 2-4 weeks after withdrawal.
Patients studied within 1 week of cocaine withdrawal but not those studied within 2-4 weeks of cocaine withdrawal had higher levels of global brain metabolism as well as higher levels of regional brain metabolism in the basal ganglia and orbitofrontal cortex than did normal subjects, probably as a consequence of less brain dopamine activity. There was also a significant relationship between the number of days since cocaine withdrawal and regional brain glucose metabolism in the orbitofrontal cortex and in the basal ganglia, and the correlations between cocaine craving and metabolic activity were significant in the prefrontal cortex and the orbitofrontal cortex.
Although the time-dependent fall in metabolic activity suggests that the higher metabolic activity observed less than a week after cocaine withdrawal may represent a nonspecific expression of drug withdrawal, the selectivity of changes in glucose metabolism for the basal ganglia and for the orbitofrontal cortex suggests that the regional metabolic changes seen in cocaine abusers during detoxification are related to changes in brain dopamine activity.
作者研究了与可卡因依赖及戒断相关的脑功能变化，以提供有关导致可卡因不可控自我给药过程的线索。
他们使用[18F]-氟脱氧葡萄糖（FDG）和正电子发射断层扫描技术，对15名诊断为可卡因滥用的门诊患者和17名正常对照者进行了脑区代谢测量。其中10名患者在最后一次使用可卡因后不到1周接受研究，5名患者在戒断2 - 4周后接受研究。
在可卡因戒断1周内接受研究的患者，而非在戒断2 - 4周内接受研究的患者，其全脑代谢水平以及基底神经节和眶额皮质的脑区代谢水平高于正常受试者，这可能是脑多巴胺活性较低的结果。可卡因戒断后的天数与眶额皮质和基底神经节的脑区葡萄糖代谢之间也存在显著关系，并且可卡因渴望与代谢活性之间的相关性在前额叶皮质和眶额皮质中显著。
尽管代谢活性随时间下降表明，在可卡因戒断后不到一周观察到的较高代谢活性可能代表药物戒断的非特异性表现，但基底神经节和眶额皮质葡萄糖代谢变化的选择性表明，可卡因滥用者在戒毒期间观察到的区域代谢变化与脑多巴胺活性变化有关。
