Satel S L, Krystal J H, Delgado P L, Kosten T R, Charney D S
Department of Psychiatry, Yale University School of Medicine, New Haven, Conn, USA.
Am J Psychiatry. 1995 May;152(5):778-83. doi: 10.1176/ajp.152.5.778.
Although cocaine is a potent serotonin (5-HT) reuptake blocker, the role of 5-HT systems in cocaine craving and relapse in humans has been unclear. The authors evaluated whether acute reductions in central 5-HT synthesis modulated craving for cocaine in cocaine-dependent patients.
Twenty-five cocaine-dependent male inpatients were exposed to cocaine-craving cues while their 5-HT levels were lowered and during a placebo condition in a counterbalanced, double-blind design. 5-HT levels were reduced by rapidly lowering plasma levels of its precursor, tryptophan; tryptophan levels were reduced by stimulating protein synthesis with a large drink of amino acids devoid of tryptophan. During the placebo condition the patients drank an identical amino acid drink containing tryptophan. Craving was induced by exposing patients to cocaine paraphernalia and a videotape depicting drug use. Craving was assessed 7 hours after ingestion of the drink. Visual analog ratings of craving for cocaine were administered before and after cue exposure at each test session.
Patients reported less desire for cocaine stimulated by cue exposure after drinking amino acids without tryptophan than they did after drinking placebo. The order that tryptophan depletion and placebo tests were performed influenced the impact of tryptophan depletion on cue-induced craving.
Serotonergic systems modulate cue-induced craving for cocaine, a factor implicated in relapse to cocaine use.
尽管可卡因是一种强效的血清素（5-羟色胺，5-HT）再摄取阻滞剂，但5-HT系统在人类对可卡因的渴望及复吸中的作用尚不清楚。作者评估了可卡因依赖患者中枢5-HT合成的急性减少是否会调节对可卡因的渴望。
25名可卡因依赖男性住院患者在5-HT水平降低时以及在平衡、双盲设计的安慰剂条件下，暴露于引发可卡因渴望的线索中。通过快速降低其前体色氨酸的血浆水平来降低5-HT水平；通过大量饮用不含色氨酸的氨基酸饮料刺激蛋白质合成来降低色氨酸水平。在安慰剂条件下，患者饮用含色氨酸的相同氨基酸饮料。通过让患者接触可卡因用具和描绘吸毒的录像带来诱发渴望。在饮用饮料7小时后评估渴望程度。在每个测试环节的线索暴露前后，对可卡因渴望进行视觉模拟评分。
与饮用安慰剂后相比，患者饮用不含色氨酸的氨基酸饮料后，线索暴露刺激产生的对可卡因的渴望程度更低。色氨酸耗竭和安慰剂测试的执行顺序影响了色氨酸耗竭对线索诱发渴望的影响。
血清素能系统调节线索诱发的对可卡因的渴望，这是一个与可卡因使用复吸有关的因素。
