Studies on clinical features of nicotine dependence in comparison with those of alcohol and methamphetamine dependence using a two compartment model of drug dependence]

The purpose of the present study was to develop a new clinical evaluation form to compare the clinical features of nicotine dependence with those associated with alcohol and methamphetamine dependence, using a two compartment model consisting of "drug dependence" and "dependence syndrome". The evaluation form consisted of six scoring items: subjective effects, tolerance, drug liking, social disturbance, withdrawal syndrome, and acute psychic and acute physical disorders. "Drug dependence" was defined by positive scores on the "drug liking" item. "Dependence syndrome" was defined by positive scores on drug-induced pathological symptoms (withdrawal syndrome, and acute psychic and physical disorders) and social disturbance. The subjects were dependent on nicotine (n = 68), alcohol (n = 62), or methamphetamine (n = 55). All subjects met DSM-IV diagnostic criteria for drug dependence. Nicotine produced a mild degree of drug liking and psychic withdrawal symptoms, but did not cause significant physical withdrawal symptoms, acute psychic or physical disorders or social disturbance. Alcohol and methamphetamine produced a moderate degree of drug liking and significant levels of withdrawal syndrome, acute disorders and social disturbance. Thus, in the present study, nicotine dependence differed from other forms of drug dependence in that nicotine was not associated with "dependence syndrome".     

Clinical features of nicotine dependence]

Nicotine dependence is characterized by weak dependence potential and less ability to produce psychotoxicity and social disturbance. A two-compartment model consisting of "dependence" and "dependence syndrome" was used to clarify clinical features of nicotine dependence. "Dependence" was defined by drug liking. "Dependence syndrome" was defined by a compulsion to take a drug, and drug-induced pathological symptoms (withdrawal syndrome and acute disorders) and social disturbance. Nicotine produced a mild or the least degree of drug liking and withdrawal syndrome, without any significant social disturbance, or acute disorders. Thus, nicotine dependence differed from other forms of drug dependence in that nicotine was not associated with "dependence syndrome". This review also introduced other current topics of nicotine dependence. First, adolescence is regarded as a risk factor for the development of nicotine dependence, whereas the involvement of gender difference (female) in this respect is controversial. Secondly, many smokers feel difficulties in quitting smoking in spite of the weak dependence potential of nicotine, which is known as the "nicotine paradox". Several working hypotheses have been presented to explain this phenomenon. For example, nicotine has relatively strong conditioning effects and/or dependence liability compared with other drugs of abuse. However, further studies should be carried out to clarify clinical characteristics of the "nicotine paradox".     

The Fagerstrom Test for Nicotine Dependence and the Diagnostic Interview Schedule: do they diagnose the same smokers?

Two common assessment tools for nicotine dependence are the Fagerstrom Test for Nicotine Dependence (FTND) and the Nicotine Dependence section of the Diagnostic Interview Schedule [(DIS)-III-R or -IV based on the Diagnostic and Statistical Manual (DSM)-III-R and -IV, respectively]. The FTND emphasizes morning smoking and overall "heaviness" of smoking. The DSM emphasizes adverse consequences, desire to cut down, and mood changes during withdrawal. We tested (1) how the DSM-III-R diagnosis of Nicotine Dependence is related to FTND score; and (2) how the (a) DSM-III-R or (b) elevated FTND score is related to longer smoking histories, greater psychiatric symptomatology, and tobacco liking scores. Retrospective chart reviews were conducted on 370 smokers, the majority (55.9%) of whom had a current DSM-III-R diagnosis of Substance Dependence other than nicotine. All subjects had completed the FTND, the DIS-III-R, the Symptom Checklist-90-Revised (SCL-90-R), and a survey on drug liking. Agreement statistics were calculated between the DSM-II-R diagnosis of Nicotine Dependence and various cutoff scores values that were assigned as thresholds for nicotine dependence on the FTND. At no cutoff score did the two instruments reliably agree; the highest kappa (at a cutoff of FTND > or = 7) was 0.205. At cutoffs above 5, the FTND diagnosed fewer cases than the DSM-III-R. Multiple regression analysis showed that DSM diagnosis was associated with greater psychiatric symptomatology on the SCL-90-R, while FTND scores were associated with greater tobacco liking. The FTND and the DSM-III-R appear to measure different aspects of the tobacco dependence process. Specifically, the FTND may provide a stronger measure of physical dependence, while the DSM may tap other domains such as awareness of dependence, behaviors resulting from that awareness, and psychiatric symptomatology. Disagreements between the FTND and the DSM are likely to become greater with the changes in the DSM-IV.     

Functional involvement of cerebral diazepam binding inhibitor (DBI) in the establishment of drug dependence

Mechanisms for formation of drug dependence and emergence of withdrawal syndrome are not yet fully understood despite of a huge accumulation of experimental and clinical data. Several clinical features of withdrawal syndrome are considered to be common (i.e., anxiety) among patients with drug dependence induced by different drugs of abuse. In this review, we have discussed the possibility of the functional involvement of diazepam binding inhibitor (DBI), an endogenous neuropeptide for benzodiazepine receptors with endogenously anxiogenic potential, in the development of drug dependence and emergence of its withdrawal symptom. The levels of DBI protein and its mRNA significantly increased in the brain derived from mice dependent on alcohol (ethanol), nicotine and morphine, and abrupt cessation of these drugs facilitated further increase in DBI expression. In the cases of nicotine- and morphine-dependent mice, concomitant administration of antagonists for nicotinic acetylcholine and opioid receptors, respectively, abolished the increase in DBI expression. Therefore, these alterations in DBI expression have a close relationship with formation of drug dependence and/or emergence of withdrawal syndrome and are considered to be a common biochemical process in drug dependence induced by different drugs of abuse.     

丁丙诺啡药物依赖性评价

目的:调查评价阿片滥用人群中丁丙诺啡(buprenorphine,Bup)的药物依赖性及滥用潜力。方法:采用询问调查方法,对戒毒机构收治的阿片依赖者进行Bup使用情况、药物依赖性及滥用潜力的调查。被调查对象为使用Bup 3天以上,无精神障碍的阿片依赖者;调查内容包括药物滥用史,Bup一般使用情况和药物依赖性评价等。Bup的身体依赖性采用30项阿片戒断症状量表(OWS)评价。根据被调查对象先前出现过的Bup戒断症状经历(及严重程度)将各项症状/体征分为0-3分进行评价。对Bup的主观欣快效应采用视觉类比量表(VAS)评价。结果:共对1235例符合条件者进行了调查。被调查者初次使用Bup目的(多选择回答)以“戒毒目的使用”(占77.4％)和“治疗稽延性戒断症状”(占26.6％)为主。30项阿片戒断症状量表(OWS)平均分值介于0.2至1.3之间,除失眠、骨关节疼痛和烦躁不安平均分值分别为1.3、1.2和1.0外,其余症状均为1分以下,表明身体依赖性低。Bup“连续使用”,“间断使用”和“有时连续,有时间断使用”三种不同使用时间方式的OWS均分分别为0.9±0.9,0.4±0.5和0.7±0.4;ANOVA方差检验F值=70.846,P<0.05,差异具有极显著性。VAS测查结果表明,VAS均值为(27±24)mm,属“轻度”至“次中等”欣快程度;对Bup含服、注射两种不同使用途径的群体进     

Smoking, nicotine dependence and psychiatric comorbidity--a population-based study including smoking cessation after three years

BACKGROUND: Evidence suggests that nicotine-dependent smokers are at increased risk for psychiatric comorbidity but general population data that included the number of nicotine dependence and withdrawal symptoms according to DSM-IV, the Fagerstrom Test for Nicotine Dependence (FTND), somatoform disorders and the number of psychiatric diagnoses are rare. The goal of the present study was to analyse relationships of smoking and nicotine dependence with psychiatric disease and whether psychiatric disease predicts the sustaining of smoking after three years. METHODS: Cohort study with a random adult population sample in a northern German region (N = 4075) including a baseline measurement of ever daily smokers aged 18-64 (n = 2458), a first follow-up of the current smokers at baseline (n = 1552) after 30 months and a second follow-up after 36 months. Measures included DSM-IV diagnoses by the Composite International Diagnostic Interview, FTND, smoking cessation by interview. RESULTS: Current daily smokers showed higher odds of a substance use disorder other than nicotine dependence compared with never smokers (odds ratio, OR, 4.6; confidence interval, CI, 2.9-7.2), affective (OR 1.8; CI 1.4-2.5), anxiety (OR 1.6; CI 1.2-2.0) or somatoform disorder (OR 1.4; CI 1.0-1.8). DSM-IV nicotine dependence and the FTND were positively related with the number of psychiatric diagnoses. Psychiatric comorbidity did not predict the maintenance of smoking or quitting. CONCLUSIONS: Findings of increased rates of mental disorders among smokers and nicotine-dependent smokers in the adult general population are supported by this study. The number of nicotine dependence and withdrawal symptoms are related to mental disorders. In addition, somatoform disorders show relationships with smoking similar to relationships with depressive or anxiety disorders. The intention to stop smoking should be proactively supported among these comorbid patients.     

北京地区三种新型毒品流行滥用特征

目的:了解北京地区发生流行性滥用的主要"新型毒品"的滥用现状、滥用特征和对个体身心及社会的危害。方法:自拟调查问卷对北京市公安局强制戒毒所2007年8月-2008年3月收治的主要吸食"冰毒"(MA)、"摇头丸"(MDMA)、氯胺酮(ketamine)的人员进行调查。结果:共调查"新型毒品"滥用人员268名,其中滥用毒品种类以MA为主139例(51.9%),以MDMA为主62例(23.1%),以氯胺酮为主67例(25.0%);被调查对象的年龄29.2±s6.3 a(最小年龄19 a,最大年龄50 a)。滥用者的职业涉及多种行业,以私营/个体劳动者(37.5%)和无业者(32.2%)为主。三种"新型毒品"滥用方式和滥用场所的特征是:"冰毒"滥用场所以家中(59.7%)为主,主要滥用方式为烫吸(98.6%);"摇头丸"滥用场所主要集中在歌舞厅(66.1%),滥用方式以口服为主(96.8%);氯胺酮滥用场所以歌舞厅为主(55.2%),滥用方式以鼻吸为主(91.0%)。滥用毒品的种类除以上述三种"新型毒品"为主外,该群体中的部分人还有"麻谷"、可卡因、大麻和海洛因滥用行为/经历。该群体95.5%在停止使用后出现不同程度、不同表现的戒断症状/体征,59.0%出现过主动或强迫性寻找和服用"新型毒品"的行为。268例"新型毒品"滥用者滥用"新型毒品"后均出现了涉及重要生命器官和精神系统不同程度的中毒症状/体征,使用"新型毒品"后体重平均减轻12.57 kg±s9.25 kg,有4.5%的滥用者发生急性中毒。有27.3%发生与使用"新型毒品"有关的冲动行为、易激惹及打架、吵架等行为,63.6%发生过使用"新型毒品"有关的性冲动,4.9%发生性暴力行为。结论:北京地区"新型毒品"滥用及其产生的健康和社会后果严重,滥用后可产生中度至次重度躯体依赖和精神依赖,精神依赖性强度强于躯体依赖性。由于其特殊的药理/毒理学作用,滥用后不仅损害了个体健康,也给社会治安带来了严重的隐患。目前北京地区正面临着继海洛因之后多种"新型毒品"流行滥用的威胁。     

Nicotine physical dependence and tolerance in the mouse following chronic oral administration

Rationale Although nicotine dependence and tolerance develop in rats, few studies have examined these processes in the mouse. Establishing such mouse models would eventually allow for an examination of the role of specific nicotinic receptor subtypes in mediating these processes (i.e. through the use of receptor knockouts).Objectives The goals of the present study were to establish mouse models of nicotine dependence and tolerance.Methods Mice were chronically exposed to nicotine (0–200 g/ml) in their drinking solution and assayed for plasma nicotine and cotinine levels, withdrawal signs following nicotine cessation (spontaneous withdrawal) or nicotinic antagonist administration (precipitated withdrawal), or nicotine tolerance. Dependence assays included somatic sign observations (paw tremors, backing and head shakes), tail-flick, plantar stimulation, elevated plus-maze and spontaneous activity. Tolerance was assayed using tail-flick, hot-plate and body temperature tests.Results Plasma nicotine and cotinine levels were elevated during oral nicotine exposure (15.85 ng/ml and 538.00 ng/ml, respectively) and quickly declined following nicotine cessation (<1 ng/ml and <2 ng/ml, respectively), providing evidence that the oral route was pharmacologically relevant. Nicotine withdrawal increased numbers of somatic signs (spontaneous and mecamylamine-precipitated withdrawal) and/or hyperalgesia (spontaneous withdrawal only). Chronic nicotine exposure also produced tolerance, as indicated by reduced responsivity to acute nicotine in assays of analgesia and hypothermia.Conclusions These results indicate that chronic oral nicotine produces dependence and tolerance in the mouse. Further, nicotine dependence may be mediated by multiple nicotinic receptor subtypes, since specific nicotinic receptor antagonists failed to precipitate withdrawal.     

Effect of three smoking cessation treatments on nicotine withdrawal in 141 abstinent alcoholic smokers

This prospective study examined the effect of three behavioral smoking interventions and reductions in cigarettes smoked per day on nicotine withdrawal symptoms in 141 abstinent alcoholic smokers (73 men, 68 women). The participants' mean +/- SD age was 41.4 +/- 9.2 years. They smoked an average of 27.7 +/- 12.1 cigarettes per day and reported 4.1 +/- 4.3 years of current abstinent from alcohol and other drugs of dependence. Participants were randomly assigned to a 12-week program of standard treatment (ST, n = 61), behavioral counseling plus exercise (BEX, n = 39), or behavioral counseling plus nicotine gum (BNIC, n = 41). All three conditions included instructions to reduce the number of cigarettes smoked per day prior to the target quit date (TQD). The TQD was week 4 for ST subjects and week 8 for those in the BEX and BNIC groups. The post-treatment assessment occurred one week after TQD. The Profile of Mood States (POMS) and the Beck Depression Inventory were administered at baseline and posttreatment to assess nicotine withdrawal. Significant increases were detected for the POMS total mood disturbance score, and the depression, tension, anger and confusion subscales, while vigor scores decreased (all p < 0.03). Withdrawal change scores were not found to be associated with treatment condition or percentage reduction in cigarettes, and there was no evidence of a significant interaction of treatment and cigarette reduction. Results are discussed in relation to implications for treatment and for future research.     

曲马朵药物依赖性和滥用潜力

AIM: To assess the drug dependence and abuse liability of tramadol. METHODS: Subjects of opiate addicts with history of tramadol abuse were 219. Physical dependence of tramadol was assessed using opiate withdrawal scale (OWS), psychic dependence was assessed by association test of Addiction Research Center Inventory-Chinese Version (ARCI-CV); the degrees of craving experienced for tramadol was self-reported on visual analogue scale (VAS). RESULTS: The scores of OWS of tramadol were 0.05-1.07; 3 scores on scales in particular being used the identify euphoric effects--MBG, sedative effects--PCAG, and psychotomimetic effects--LSD of ARCI were 7.3, 6.1, and 3.4, respectively (F = 38.1, P < 0.01); 57.1% of tramadol abuse subjects had craving for tramadol (chi 2 = 75.86, P < 0.01). CONCLUSION: Tramadol produced high abuse potential among opiate addicts.     

Levels of opioid physical dependence in heroin addicts

The levels of opioid physical dependence in a group of long-term heroin addicts were ascertained by measuring the severity of the opioid withdrawal syndrome before and after pharmacological challenge with either 0.4 mg naloxone or placebo. Prior to challenge, patients manifested some subjective symptoms but few objective signs of opioid withdrawal. Patients who received placebo (n = 18) showed a significant increase in the mean score on one of three rating scales used to assess opioid withdrawal. Patients who received naloxone (n = 58) showed significant increases in mean scores on all three rating scales, but this was due primarily to increases observed in a minority of patients. Sixty-one percent of patients failed to manifest clinically significant changes in subjective symptoms, and 74% of patients failed to manifest clinically significant changes in objective signs of opioid withdrawal following naloxone administration. The results suggest that a substantial subgroup of heroin addicts are able to use opioids regularly while maintaining relatively low levels of physical dependence.     

The beta-lactam antibiotic ceftriaxone inhibits physical dependence and abstinence-induced withdrawal from cocaine, amphetamine, methamphetamine, and clorazepate in planarians

Ceftriaxone (a beta-lactam antibiotic) has recently been identified as having the rare ability to increase the expression and functional activity of the glutamate transporter subtype 1 (GLT-1) in rat spinal cord cultures. GLT-1 has been implicated in diverse neurological disorders and in opioid dependence and withdrawal. It has been speculated that it might also be involved in the physical dependence and withdrawal of other abused drugs, but demonstration of this property can be difficult in mammalian models. Here, we demonstrate for the first time using a planarian model that ceftriaxone attenuates both the development of physical dependence and abstinence-induced withdrawal from cocaine, amphetamine, methamphetamine, and a benzodiazepine (clorazepate) in a concentration-related manner. These results suggest that physical dependence and withdrawal from several drugs involve a common - beta-lactam-sensitive - mechanism in planarians. If these findings can be shown to extend to mammals, beta-lactam antibiotics might represent a novel pharmacotherapy or adjunct approach for treating drug abuse or serve as a template for drug discovery efforts aimed at treating drug abuse, recovery from drug abuse, or ameliorating the withdrawal from chronic use of therapeutic medications.     

On the development of nicotine dependence in adolescence

Little is known about the natural history of drug dependence. This article describes the development and predictors of DSM-IV nicotine dependence in adolescence when tobacco use is initiated. In a two-stage design, a survey was administered to 6th-10th graders in the Chicago Public Schools to select a cohort of adolescents. Household interviews were conducted with adolescents five times and with one parent (predominantly mothers) three times over 2 years. The analytical sample includes 353 youths, who started using tobacco within 12 months preceding Wave 1 or between Waves 1-5. Survival analysis estimated latency to individual DSM-IV nicotine dependence criteria and the full dependence syndrome. Twenty-five percent of youths experienced the syndrome within 23 months of tobacco use onset. Tolerance, impaired control and withdrawal were experienced most frequently. Youths who developed full dependence experienced their first symptom faster after tobacco use onset than those who experienced only one criterion through the end of the observation period. Cox proportional hazards models estimated the importance of time-constant and time-varying sociodemographic, tobacco and other drug use, parental and peer smoking, social psychological and biological risk factors for experiencing the first criterion and the full syndrome. Pleasant initial sensitivity to tobacco and number of cigarettes smoked the prior month predicted both outcomes. Parental dependence predicted the full syndrome. Significant covariates were generally the same across gender and racial/ethnic subgroups. The predictive significance of the initial smoking experience and parental dependence highlight the potential importance of genetic factors in the etiology of nicotine dependence.     

Opioid physical dependence development: effects of single versus repeated morphine pretreatments and of subjects' opioid exposure history

In acute dependence, signs and symptoms of opioid withdrawal are precipitated when an opioid antagonist (naloxone) is administered following acute (e.g. single dose) pretreatment with amu agonist. This study examined the influence of amount of previous opioid exposure, both immediate and remote, on intensity of precipitated withdrawal effects in an acute dependence model. Two groups of subjects, opioid abusers (n=20) and nonabusers (n=20), received either one 15 mg/70 kg IM morphine pretreatment or two such pretreatments spaced 24 h apart. Naloxone challenge (30 mg/70 kg) followed 4.33 h after the second pretreatment. There were clear effects of morphine pretreatment condition (single versus repeated 15 mg) on the intensity of precipitated withdrawal responses elicited by naloxone. More intense effects were seen after the repeated pretreatment, suggesting that physical dependence escalates with repeated opioid exposures spaced at appropriate intervals. Subjects with an opioid abuse history reported greater liking of agonist drug effects than did nonabusers, whereas nonabusers reported more sedating effects. However, an opioid abuse history did not influence the intensity of precipitated withdrawal symptoms and signs. The latter finding suggests that a previous opioid exposure history does not dramatically modulate initial stages of physical dependence development during subsequent opioid exposure episodes.This research was supported by USPHS Grant DA04011 and Research Training Grant T32 DA07209 from the National Institute on Drug Abuse     

A simple,reliable method for predicting the physical dependence liability of narcotic antagonist analgesics in the rat

The rat intraperitoneal infusion procedure was used to chronically administer drugs for evaluation of the physical dependence liability of narcotic antagonist analgesics. Three methods were used to assess dependence liability: presence of withdrawal signs upon abrupt cessation of chronic infusion (primary dependence), attenuation of the withdrawal signs produced by cessation of chronic morphine infusion (morphine substitution), and production of withdrawal signs when chronically morphine-infused rats were administered the drugs (precipitated withdrawal). Butorphanol, nalbuphine and pentazocine all caused a mild withdrawal in the rat primary dependence model which agrees with the conclusions from experiments with monkey and man. None of these agents substituted for morphine in the rat and all three appeared to precipitate withdrawal. Two experimental drugs, Codorphone and TR5400, did not induce primary dependence in the rat, and in chronic-morphinized rats, they precipitated a withdrawal syndrome comparable to naloxone. Another experimental drug, TR5257, substituted for morphine. The correlation between these observations in the rat and previously published data from the monkey are excellent. It is proposed that the rat could be used as a reliable indicator of potential physical dependence liability for the narcotic antagonist analgesics.     

Overview of the progress in drug dependence studies--mainly focussing on psychic dependence]

The technical term 'drug dependence' was officially adopted by WHO's Expert Committee on Addiction in 1964. Until this, to describe a state of dependence, terms such as 'poisoning', 'habit', 'ism', and 'addiction' had been used from time to time. Until the 1950's, investigators were mainly focussed on the phenomena of physical dependence. However, once the concept of psychic dependence had been introduced, behavioral and neuropharmacological studies on the modes of drug action that produce psychic dependence were activated and have progressed in the last two decades, and among the points clarified by these studies are the following: 1. The critical drug properties that produce psychic dependence are those of rewarding subjective and reinforcing effects of drugs but these effects are not the properties that produce physical dependence, although the development of physical dependence on particular drugs such as opiates may substantially enhance craving for the drugs. 2. The mesolimbic and mesocortical dopamine systems in the brain and also the N. Accumbens play a primary or at least a partial role in producing the subjective and reinforcing effects of major dependence-producing drugs such as cocaine, opiates, barbiturates, benzodiazepines, and ethanol. 3. Many drugs such as naltrexone, methadone, and some dopamine antagonists and serotonin reuptake inhibitors or antagonists were found to be effective in the pharmacotherapy of the dependence on opiates, cocaine, or ethanol.     

Physical dependence increases the relative reinforcing effects of caffeine versus placebo

Using a within-subject cross-over design, this study examined the role of physical dependence in caffeine reinforcement by experimentally manipulating physical dependence. Each subject was exposed to two chronic drug phases (300 mg/70 kg/day caffeine and placebo) for 9–12 days, with order of phases counterbalanced across subjects. On 2 separate days immediately following each of the chronic drug exposures, subjects received acute doses of either caffeine (300 mg/ 70 kg) or placebo in counterbalanced order. The reinforcing effects of these drugs were then determined by using a multiple-choice procedure in which subjects made a series of discrete choices between receiving varying amounts of money or receiving the drug again, and a choice between the two drugs. To ensure that subjects completed the form carefully, following exposure to both of the acute drug administrations, one of the subject’s previous choices from the multiple-choice form was randomly selected and the consequence of that choice was implemented. When subjects were maintained on chronic caffeine, they were willing to forfeit significantly more money and showed significant increases in typical withdrawal symptoms (e.g. fatigue, mood disturbance) after receiving placebo as compared to the other three conditions. When subjects were maintained on chronic caffeine, they also chose to receive caffeine over placebo twice as often than when they were maintained on chronic placebo. These findings provide the strongest evidence to date indicating that caffeine physical dependence increases the relative reinforcing effects of caffeine versus placebo. Received: 1 June 1997/Final version: 3 February 1998     

The quantitative assessment of physical dependence on opiates

A procedure for administering naloxone to narcotic-dependent individuals and a technique for quantitating the ensuing acute withdrawal syndrome have been developed to assess the degree of physical dependence. Successive injections of increasing doses of naloxone produce a controlled increase in severity of withdrawal signs and symptoms as measured by a subjective and an objective assessment battery. There is good agreement between the subjective and objective assessments and a global rating of withdrawal severity. The objective measures are, however, most sensitive and produce a withdrawal syndrome score related to the duration of the current cycle of drug abuse. Hand tremor, trapezius electromyogram and heart rate are the most sensitive signs of withdrawal and can be used in combination to form the basis of a simplified and shortened antagonist assessment test for physical dependence.     

Validation of the nicotine dependence syndrome scale (NDSS): a criterion-group design contrasting chippers and regular smokers

The nicotine dependence syndrome scale (NDSS) is a new multi-dimensional measure of nicotine dependence, yielding five scores for different aspects of dependence as well as a total score. In this study, we tested the NDSS in a young adult sample (mean age=24), using an extreme-groups comparison between non-dependent smokers (chippers, n=123) and regular smokers (n=130). Scores on each NDSS subscale strongly discriminated between the groups, with the NDSS-total discriminating them almost perfectly. The subscales were generally independent discriminators, demonstrating the discriminant validity of the subscales. NDSS scales also discriminated levels of intake and dependence within the chippers group, suggesting that the scales were sensitive to individual differences even at the very low end of the dependence continuum.     

盐酸二氢埃托啡依赖性潜力的进一步探讨

盐酸二氢埃托啡(DHE)是一种新的强效麻醉性镇痛药,本文着重对DHE在啮齿类动物Do及舌下给药条件下的自然戒断,替代吗啡,催促戒断等方面的致依赖性潜力进行了研究,结果表明,DHE的致身体依赖性潜力确实较低;以DHE替代吗啡抑制阿片类戒断症状时舌下给药剂量低于po给药剂量;在一定剂量条件下DHE舌下给药可使实验动物对其产生身体依赖性。