The ACT heroin trial: intellectual, practical and political challenges

An array of intellectual, practical and political challenges will be faced both if the Australian Capital Territory "heroin trial" does or does not eventuate. The intellectual challenges include the development of new methodologies and analytical tools for some of the outcome measures; the further development of a research process which involves all the relevant disciplines and interest groups; and capitalizing on an unprecedented opportunity to investigate the pharmacokinetics of heroin. The practicalities of setting up a trial also present a number of challenges, as does incorporating a health development approach. Political challenges include getting a sensible decision made about the trial, avoiding capture of the debate by supporters or opponents of drug law reform and avoiding unrealistic expectations. The major challenge if the trial does not go ahead is to implement other well-considered proposals which can be carefully evaluated.     

Heroin in the United Kingdom: different forms, different origins, and the relationship to different routes of administration

Heroin exists in the United Kingdom in several different forms, which vary not only in their country of origin and purity, but also in their suitability for use by either injecting or by 'chasing the dragon'. The availability of these different forms of heroin has varied considerably over time. A review of the characteristics and availability of these various forms of heroin in recent years is presented, accompanied by consideration of their probable intended use by injection or by 'chasing the dragon'. Samples of black market heroin in the salt form are usually used by injection, whereas the base form is usually taken by 'chasing the dragon'. The heroin yield to the drug user from samples of heroin taken by 'chasing the dragon' varies according to its base or salt format and according to the presence of other drugs in the sample. Heroin samples from different countries of production mostly conform to either base or salt form. Novel approaches at the macro level to prevention and control of heroin-related problems through influence upon this complex heroin market-place should now be considered.     

Lasting reduction in mesolimbic dopamine neuronal activity after morphine withdrawal

The activity of mesolimbic dopaminergic neurons was investigated in rats at various times after a chronic regimen of morphine, which produced, upon suspension, a marked somatic withdrawal syndrome. Single-cell extracellular recording techniques, coupled with antidromic identification from the nucleus accumbens, were used to monitor neuronal activity while behavioural observations allowed quantification of the somatic signs of morphine withdrawal. Temporal correlation of electrophysiological indices, such as firing rate and burst firing, with scores obtained through behavioural assessments proved negative, in that somatic signs were pronounced at 24 h after suspension of treatment and then subsided to control values at 72 h after the last morphine injection. In contrast, the firing rate and burst firing of mesolimbic dopaminergic neurons were found to be reduced at 1, 3 and 7 days after morphine withdrawal. After 14 drug-free days, electrophysiological analysis revealed an apparent normalization of various parameters. However, at this time, intravenous administration of morphine produced an increment of electrical activity which was significantly higher than that obtained in control (saline treated) rats. Further, administration of the opiate antagonist naltrexone, administered without prior morphine, at 3, 7 and 14 days after the last morphine administration, failed to alter dopaminergic neuronal activity. The results indicate: (i) that the activity of mesolimbic dopaminergic neurons remains reduced well after somatic signs of withdrawal have disappeared; (ii) after 14 days of withdrawal, the augmented magnitude of the electrophysiological response to exogenous morphine suggests an increased sensitivity of opiate receptors; and (iii) the lack of relationship between dopaminergic activity and somatic signs of withdrawal corroborates the notion that dopaminergic activity in the mesolimbic system does not participate in the neurobiological mechanisms responsible for somatic withdrawal. The present results may be relevant to the phenomenon of drug addiction in humans and consequent relapse after drug-free periods.     

Running and cocaine both upregulate dynorphin mRNA in medial caudate putamen

Physical activities such as long-distance running can be habit forming and associated with a sense of well-being to a degree that justifies comparison with drug-induced addictive behaviours. To understand molecular similarities and dissimilarities controlling these behaviours in humans we compared the effects of running in running wheels to the effects of chronic cocaine or morphine administration on mRNA levels in brain reward pathways in the inbred Fischer and Lewis rat strains. These strains are both inbred from the Sprague-Dawley strain; Lewis rats display a higher preference towards addictive drugs and running than do Fischer rats. After chronic cocaine or running a similar increase of dynorphin mRNA in medial caudate putamen was found in the Lewis rat, suggesting common neuronal adaptations in this brain region to both cocaine and running. Fischer and Lewis rats both responded to cocaine with increased dynorphin mRNA levels in medial caudate putamen. However, only Lewis rats increased dynorphin mRNA after running, possibly reflecting the much higher degree of running by the Lewis strain as compared to the Fischer strain. Moreover, the running-induced upregulation of dynorphin mRNA was blocked by the opioid receptor antagonist naloxone. We suggest that running increases dynorphin mRNA by a mechanism that involves endogenous opioids. The voluntary wheel-running model in rats might be used to study natural reward and compulsive behaviours and possibly also to screen candidate drugs for treatment of compulsive disorders.     

阿片成瘾严重程度量表的初步编制与信度测试

目的 :编制阿片成瘾严重程度评定量表 ,并对量表进行信度检验。方法 :参考相关文献自行设计“2 8项阿片成瘾严重程度量表”( 2 8ItemsOpioidAddictionSeverityInventory ,OASI - 2 8) ,对北京市某戒毒治疗机构收治的 6 0例海洛因成瘾者进行结构性访谈。通过小样本预试验 ,采用同质性信度与重测信度对量表进行信度评价。结果 :同质性信度 :除家庭后果一项外 ,其余各因子及量表总的Cronbach’sα系数在 0 .5 2 44～ 0 .8140之间。各症状项目分与总分的相关性除第 1题 (从第一次吸毒时间到成瘾的时间 )、第 15题 (体重变化 )和第 2 1题 (吸毒后工作情况 )外 ,余者的P值均 <0 .0 5。重测信度 :总量表及各因子的重测相关系数介于 0 .476～ 0 .895之间 (P <0 .0 1)。结论 :本量表有较好的同质性信度和重测信度。     

对贵阳市100例女性吸毒者的艾滋病知识、态度调查

目的:了解女性吸毒者对艾滋病的态度和相关知识掌握情况。方法:对2000年在贵阳市公安局戒毒中心强制戒毒的100名女性海洛因依赖者进行匿名问卷调查。结果:该吸毒群体中以烫吸方式滥用毒品者占81.0％,静脉注射方式占7.0％,烫吸、静脉注射混用方式占12.0％;与他人合用过注射器的占静脉注射者的47.4％;知道艾滋病是传染病的占93.0％;知道共用注射器可以传播艾滋病的占83.0％;知道孕妇可将艾滋病病毒传染给胎儿的占50.0％;知道艾滋病病毒主要侵害免疫系统的占31.0％;知道艾滋病是可预防的占63.0％;知道艾滋病是不可治愈的占49.0％;知道安全套可预防艾滋病感染的占34.0％,对预防艾滋病所采取的保护措施的应答中,肯定应答率最高的一项为35.0％。结论:本调查显示,贵阳地区女性吸毒者对艾滋病的传播方式仍缺乏全面了解,对预防知识的了解仍很贫乏,提示在该群体中进行艾滋病知识的宣传、教育和行为干预,对遏制艾滋病的传播、减少危害有极其重要的意义。     

海洛因依赖者住院脱毒过程中的不良事件及其相关因素分析

目的:了解海洛因依赖者住院脱毒过程中出现的不良事件及其相关因素。方法:采用回顾性的方法,对630例海洛因依赖者在住院脱毒过程中出现的各种不良事件进行调查,并对相关因素进行分析。结果:不良事件的总发生率为17.6％。Logistic回归分析显示,整组不良事件患者的危险因素不明确。按不良事件的严重程度归类分组分析,其危险因素依次为:美沙酮最高剂量,血常规异常,合用抗精神病药物的种类以及目前吸食方式。结论:海洛因依赖者住院脱毒过程中不良事件较常见,它的发生既有患者自身的原因,又有医源性因素,值得重视。     

美沙酮合并丁丙诺啡和东莨菪碱脱毒治疗

目的：比较美沙酮脱毒疗程早期改用丁丙诺啡合并东莨若碱替代治疗与单用美沙酮替代治疗方法之优劣。方法：108例符合DSM—IV阿片类依赖的戒毒者随机分为试验组和对照组，试验组于美沙酮脱毒疗程早期(第四天)改用丁丙诺啡合并东莨若碱替代治疗，对照组则单用美沙酮替代治疗。采用《阿片类药物戒断症状量表》(owS)评定疗效。结果：试验组和对照组的脱毒率分别为94．4％和74％，有显著性差异(P＜0．01＝。owS量表总分在治疗d1—4无显著性差异(P＞0．05)；在治疗d5—8，试验组总分平稳下降，与对照组逐日比较有显著性差异(P＜0．05或P＜0．01＝；治疗药物停用48h后试验组症状未见波动，而对照组症状波动，owS总分两组间有显著性差异(P＜0．01＝。结论：美沙酮脱毒疗程早期改用丁丙诺啡合并东莨若碱替代治疗优于单用美沙酮，是快速脱毒、提高脱毒成功率的较好方法。     

The Role of Therapeutic Alliance in Network Therapy: A Family and Peer Support-Based Treatment for Cocaine Abuse

The therapeutic alliance is a well-studied construct factor that is important to outcome in many forms of individual therapy. Therapeutic alliance has been rarely studied in group therapy and results in addiction treatment have been mixed. In this paper, we studied the presence of a therapeutic alliance in Network Therapy: an approach that uses peer and family support in addiction treatment. Twenty-one participants undergoing Network Therapy for cocaine addiction were observed on videotape, and were rated on therapeutic alliance using the Working Alliance Inventory and the Penn Helping Alliance Rating Scale. Results showed a significant positive correlation between therapeutic alliance and outcome as measured by the percentage of cocaine-free urine toxicology screens and by eight consecutive cocaine-free urines.