Rush C R, Sullivan J T, Griffiths R R
Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
J Pharmacol Exp Ther. 1995 Apr;273(1):351-8.
The present study was conducted to examine the self-reported (i.e., subjective) and physiological effects of intravenous caffeine in 10 subjects with histories of stimulant drug abuse. Under double-blind conditions, subjects received each dose of caffeine (0, 37.5, 75, 150 or 300 mg/70 kg) twice according to a latin-square design; injections were 10 sec in duration and separated by at least 24 hr. Effects were measured before injection and repeatedly afterward for 60 min. Caffeine dose-dependently increased ratings of positive mood (e.g., increased ratings of drug liking and high), which peaked at 2 min after injection and progressively decreased. Caffeine also dose-dependently increased the frequency of stimulant identifications on the Pharmacological Class Identification Questionnaire (e.g., like cocaine, amphetamine). Caffeine also produced negative-mood effects (e.g., increased ratings of bad effects) and increases in self-reported desire for cocaine. In contrast to the positive-mood effects, the negative-mood effects were of smaller magnitude and only significant at the highest dose. Caffeine increased reports of unusual smells and tastes. Caffeine decreased heart rate (7 bpm) and skin temperature (4 degrees C), and increased systolic and diastolic blood pressures (8 and 6 mm Hg, respectively). The mood effects but not the physiological effects of intravenous caffeine were similar to those previously observed with cocaine in studies using similar methods and subjects. Intravenous caffeine administration may provide a useful model system for investigating factors relevant to the use and abuse of stimulant drugs.
本研究旨在考察静脉注射咖啡因对10名有兴奋剂药物滥用史的受试者的自我报告（即主观）效应和生理效应。在双盲条件下，受试者按照拉丁方设计接受每种剂量的咖啡因（0、37.5、75、150或300 mg/70 kg）两次；注射持续10秒，间隔至少24小时。在注射前及注射后60分钟内反复测量效应。咖啡因剂量依赖性地增加了积极情绪评分（如对药物喜好和兴奋感的评分增加），在注射后2分钟达到峰值，随后逐渐下降。咖啡因还剂量依赖性地增加了药理类别识别问卷上兴奋剂识别的频率（如类似可卡因、安非他命）。咖啡因还产生了消极情绪效应（如不良效应评分增加），并增加了自我报告的对可卡因的渴望。与积极情绪效应相反，消极情绪效应的程度较小，仅在最高剂量时显著。咖啡因增加了异常气味和味道的报告。咖啡因降低了心率（7次/分钟）和皮肤温度（4摄氏度），并增加了收缩压和舒张压（分别为8和6毫米汞柱）。静脉注射咖啡因的情绪效应而非生理效应与之前在使用类似方法和受试者的研究中观察到的可卡因的效应相似。静脉注射咖啡因可能为研究与兴奋剂药物使用和滥用相关的因素提供一个有用的模型系统。
