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目的研究吗啡依赖和戒断时大鼠杏仁核中神经甾体和氨基酸递质水平的变化。方法连续7天给予大鼠盐酸吗啡建立吗啡依赖模型。使用纳洛酮(2mg/kg)催促戒断,观察戒断症状并进行评分。将大鼠断头处死后,剥离大脑并分离出杏仁核,用液-液萃取和固相萃取法提取游离型和结合型神经甾体。神经甾体(包括脱氢表雄酮、孕烯醇酮、别孕烯醇酮、脱氢表雄酮硫酸酯和孕烯醇酮硫酸酯)的含量使用高效液相色谱-质谱法测定。甘氨酸、谷氨酸和γ-氨基丁酸的含量采用柱前OPA衍生-电化学检测-高效液相色谱法测定。结果与盐水对照组相比,吗啡依赖大鼠杏仁核中的脱氢表雄酮水平降低33 %(P<0·01)。与戒断对照组比较,吗啡戒断大鼠杏仁核中的孕烯醇酮和别孕烯醇酮水平分别升高45 %和42 %(P<0·05) ,γ-氨基丁酸水平降低18 %(P<0·01)。与吗啡依赖组比较,吗啡戒断组大鼠杏仁核中的孕烯醇酮和孕烯醇酮硫酸酯水平分别升高60 %和40 %(P<0·05) ,甘氨酸水平降低14 %(P<0·05)。结论吗啡依赖大鼠杏仁核中的脱氢表雄酮可能参与吗啡依赖的形成而与吗啡戒断症状的表达无关。其他神经甾体(包括孕烯醇酮、别孕烯醇酮和孕烯醇酮硫酸酯)则可能参与吗啡的戒断而与依赖的形成无关。纳洛酮催促戒断时,大鼠杏仁核中抑制性氨基酸递质的合成和释放受到抑制。表明大鼠杏仁核中的各种神经甾体和氨基酸递质在吗啡依赖和戒断时发生了不同的变化。  相似文献   
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小鼠吗啡依赖纳洛酮催促戒断跳跃反应模型的建立   总被引:1,自引:0,他引:1  
目的建立稳定的小鼠吗啡依赖纳洛酮催促戒断跳跃反应模型。方法小鼠连续皮下注射吗啡,以纳洛酮催促戒断跳跃反应为指标,调整吗啡给予天数(5,6,7,10d)、吗啡累积剂量(360,560,640,945,1100,1105,1200mg/kg)、每日给予吗啡的频数[一天二次(bid),一天三次(tid)]、纳洛酮催促紧前给予吗啡与否、以及纳洛酮剂量(10,20mg/kg),建立四个造模方案包括八个子方案。结果方案A、B2、C2吗啡组小鼠跳跃反应率未达100%;方案B1、C1、D2、D3、D4吗啡组小鼠跳跃次数变异系数较大。方案D1采用小鼠连续皮下注射倍增剂量的吗啡,tid×6d,每日每次剂量分别为5,10,20,40,80,160mg/kg;第7天皮下注射吗啡160mg/kg,3h后腹腔注射纳洛酮10mg/kg,吗啡组小鼠可产生显著的跳跃反应,与对照组比较差异有显著性(P<0.01),且变异系数小(CV为0.22),该方案吗啡依赖小鼠跳跃反应次数适度,离散度小。结论选用方案D1可建立稳定的小鼠戒断跳跃反应模型。  相似文献   
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BACKGROUND: Personality traits are associated with substance dependence (SD); genetic factors may influence both. Strong associations between ADH4 variation and SD have been reported. We aimed to investigate the relationship between ADH4 variation and personality traits in the present study. METHODS: We assessed dimensions of the five-factor model of personality in 243 subjects with SD (175 European Americans [EAs] and 68 African Americans [AAs]) and 296 healthy control subjects (256 EAs and 40 AAs). We also genotyped 7 ADH4 markers (spanning the locus) and 38 unlinked ancestry-informative markers in these subjects. The relationships between the diplotypes, alleles, and genotypes at ADH4 and personality traits were examined using multivariate analysis of covariance (MANCOVA), controlling for potential confounders. RESULTS: Generally, SD patients, older individuals, and male subjects scored higher on neuroticism and lower on other personality factors. Personality factors were associated with the diplotypes. The allele A or genotype A/A of single nucleotide polymorphism (SNP)6 (rs1800759 at the gene promoter) was significantly associated with agreeableness scores. There were associations between extraversion and SNP1 (hcv2033010 at the 3' end) and SNP2 (rs1042364 in exon 9) in subjects with higher conscientiousness scores. CONCLUSIONS: The personality traits of agreeableness and extraversion are related to ADH4 polymorphism. Among the ADH4 markers that appear to predispose to certain personality traits, the functional variant rs1800759 (SNP6) in the promoter region is most important. We conclude that personality traits and SD have a partially overlapping genetic basis.  相似文献   
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Buprenorphine is a mu opioid partial agonist currently used as an analgesic, and being developed for the treatment of opioid dependence. The purpose of this study was to determine the abuse liability of parenteral buprenorphine in volunteers maintained on daily sublingual (SL) buprenorphine (8 mg). In a residential laboratory, eight volunteers underwent pharmacologic challenges two times per week. Medication challenges were 16 h after the daily dose of buprenorphine, and consisted of double-blind IM injections of buprenorphine (4, 8, 16 mg), the prototypic mu opioid agonist hydromorphone (9 and 18 mg), or saline. Assessments consisted of physiologic monitoring, subjects’ self-reports, and a trained observer’s ratings of drug effects, and were collected for 0.5 h before and 2.0 h following injection. Supplemental doses of IM buprenorphine produced opioid agonist-like effects, indicating some abuse potential of parenteral buprenorphine in buprenorphine-maintained patients. There was incomplete cross-tolerance to the effects of hydromorphone, suggesting that higher maintenance doses of buprenorphine may be needed to maximize clinical efficacy. However, there was a lack of graded dose-effects for hydromorphone, suggesting that buprenorphine’s combination of partial agonist effects and high affinity for opioid receptors may limit the magnitude of effects of supplemental full agonists. Finally, participants tolerated cumulative doses of maintenance buprenorphine plus challenge buprenorphine without adverse effects, suggesting higher doses of buprenorphine can be safely administered to opioid dependent patients. Received: 22 February 1996/Final version: 23 August 1996  相似文献   
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We compared nicotine dependence and withdrawal in male alcoholic and control ever-smokers, controlling for relevant demographic and clinical variables. Alcoholics were more likely to meet criteria for moderate or severe nicotine dependence and endorse more nicotine dependence symptoms. Symptoms reported more frequently by alcoholics included: (a) using nicotine in larger amounts or over a longer time than intended; (b) continued use despite problems caused or exacerbated by nicotine; (c) marked tolerance; and (d) experiencing characteristic nicotine withdrawal symptoms. Alcoholics also smoked more heavily. Other than “headaches,” and “decreased heart rate,” alcoholics consistently endorsed nicotine withdrawal symptoms at a higher rate. After controlling for demographic and clinical variables and level of nicotine dependence, only “feel depressed” differed significantly between groups. Our research supports previous findings suggesting that nicotine dependence is more severe in those with a history of alcohol dependence. As a result, alcoholics may experience greater discomfort from nicotine withdrawal upon smoking cessation.  相似文献   
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The development of a unifying framework for conceptualizing the commonalities in various forms of substance abuse must encompass the data base focused upon the stimulus functions of drugs. In the first instance, for example, the research on drug self-administration has provided convincing evidence of a remarkable concordance between laboratory animals and human substance abusers in the reinforcing stimulus functions of a range of chemical agents. The recognition of these cross-species and cross-drug generalities has radically changed conceptualizations of substance abuse from a reactive to a more active process and has encouraged the kind of functional analysis of drug-seeking and drug-taking that has proven productive and useful in the study of other behavioral interactions. In this regard as well, recent refinements in the analysis of the discriminative stimulus functions of drugs have provided a more comprehensive basis for characterizing a chemical agent's spectrum of action and evaluating its abuse liability. While the correlation between the discriminative stimulus functions and the reinforcing stimulus functions is remarkably high for some drug classes, there are notable exceptions. Finally, the assessment of abuse liability requires an analysis of the eliciting stimulus functions of drugs as reflected by the physiological and behavioral changes, both acute and chronic, that follow drug administration. The methods used to evaluate both physiological dependence and behavioral toxicity in relationship to sensory and motor effects for a range of abused drugs have depended heavily upon an assessment of the eliciting stimulus functions of such compounds.  相似文献   
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135例海洛因依赖者乙型肝炎病毒标志检测结果分析   总被引:2,自引:0,他引:2  
135例海洛因依赖者乙型肝炎病毒标志检测结果分析张立学,郑纳新,赖倩(解放军307医院.北京.100039)摘要**本文对135例海洛因依赖者做乙型肝炎病毒(HBV)标志物栓测,结果显示:HBV感染阳性率为65.9%,HBsAg阳性携带率为7.4%....  相似文献   
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