Protective Effect of Oral Acetylcysteine against the Hepatorenal Toxicity of Carbon Tetrachloride Potentiated by Ethyl Alcohol

Considering the well-documented protection of acetylcysteine (AC) in hepatotoxicity related to acetaminophen, we studied the preventive potential of AC against mild hepatotoxicity of CCl4, potentiated with ethyl alcohol (ETH) and the role of tissue glutathione. Rats fed a liquid diet with 30% of energy from ETH, had-intraperitoneal CCl4 administered in three injections, at 7-day intervals. AC was ingested at the level for acetaminophen overdose. ETH markedly potentiated the injury induced by CCl4, as evidenced by higher values of serum alanine aminotransferase (ALT), urinary bile acids (BA), serum creatinine, histological score of liver cell necrosis, mortality and by lower body weights and lower liver glutathione, when compared with CCl4 alone. Protective effect of AC consisted of a lesser hepatocytic necrosis, better body weights and higher liver glutathione. We conclude, that AC favorably modifies liver damage induced by CCl4 and potentiated with ETH. There is a preventive role for AC in subjects who combine ETH overuse with exposure to hepatotoxic xenobiotics, whose toxicity is modified by tissue glutathione.     

Comparative PET studies of the kinetics and distribution of cocaine and cocaethylene in baboon brain.

Recent studies have suggested that cocaethylene, an active metabolite of cocaine found in blood and postmortem brain of individuals self-administering cocaine and alcohol, may play a role in the increased toxicity seen when coadministering these 2 drugs. We have used positron emission tomography (PET) and carbon-11 (t1/2:20.4 min) labeled cocaine and cocaethylene to compare the short-term kinetics of cocaine and cocaethylene in baboon brain. The regional uptake of [11C]cocaine cocaethylene in baboon brain. The regional uptake of [11C]cocaine ([11C]COC) and [11C]cocaethylene ([11C]CE), 5-8 mCi and 4-6 micrograms, in baboon brain (n = 7) were similar but clearance from whole brain (global, GL) and from striatum (SR), thalamus (TH), and cerebellum (CB) was slower for cocaethylene. Steady-state distribution volumes (DV) were not significantly different in the striatum but were greater for cocaethylene in the thalamus, cerebellum, and whole brain. Debenzoylation of cocaethylene proceeded at about one-third the rate of cocaine, as determined by in vitro incubation of labeled cocaethylene and labeled cocaine with baboon plasma and with purified horse butyryl-cholinesterase (EC 3.1.1.8). Even though the slower clearance of cocaethylene could lead to longer tissue exposures and potentially accentuated or different physiological effects relative to cocaine, the difference between the 2 drugs is not large. Thus it is more likely that the direct actions of cocaine and alcohol on some organs, rather than cocaethylene, account for this enhanced toxicity.     

中国蒙,汉族酒依赖与醇脱氢酶和醛脱氢酶基因多态性的相关研究

为探讨醇脱氢酶（ＡＤＨ）基因和醛脱氢酶（ＡＬＤＨ）基因多态性与酒依赖患病的相互关系，用耳血干血痕聚合酶链反应、等位基因特异性寡核苷酸探针方法，检测乙醇代谢酶ＡＤＨ和ＡＬＤＨ基因型在我国蒙、汉民族酒依赖与非酒依赖者中分布频率。结果显示在酒依赖组（汉族５２例，蒙族３１例）与正常对照组（汉族４８例，蒙族３５例）之间：汉族的ＡＬＤＨ２基因型频率与等位基因频率的分布差异有非常显著性（Ｐ＜０．０１），而蒙族则表示为ＡＤＨ２基因型频率与等位基因频率的分布差异有非常显著性（Ｐ＜０．０１）。这提示汉族酒依赖的发病与ＡＬＤＨ２基因有关，蒙族则与ＡＤＨ２基因有关。     

重庆地区驾驶员血液中乙醇浓度与驾驶能力的关系

目的　探讨重庆地区驾驶员血液中乙醇浓度 (BAC)和驾驶能力的关系 ,为交通安全立法提供科学依据。　方法　随机选择重庆地区 59名驾驶员志愿者 ,建立饮酒后驾车模型、科学的BAC测定以及驾驶能力评价体系 ,对不同BAC下驾驶能力进行测评。　结果　受试者出现驾驶能力损害时的BAC均数为 685.9mg/L ,最小值 190 .0mg/L ,最大值 152 0 .0mg/L ,总体均数 95%可信区间为 60 2 .4～ 70 9.5mg/L。汉族和土家族间、汉族男性和女性间、2 3～ 3 5岁和 3 6～ 56岁年龄组间差异无显著性意义 (P >0 .0 5) ,而既往饮酒量不同的三个组别间差异有显著性意义 (P <0 .0 5)。随着BAC增高 ,驾驶能力受损人数增加。在 2 0 0 .0mg/L有 3 % (2 / 59)的受试者驾驶能力降低 ,80 0 .0mg/L则达到 68% (40 / 59)。　结论　随着BAC增高 ,重庆地区驾驶员驾驶能力受损人数比例增加 ,出现驾驶能力明显损害时BAC为 60 2 .4～ 70 9.5mg/L ,既往酒量较大人群中该值较高     

Ethanol and nicotine consumption and preference in transgenic mice overexpressing the bovine growth hormone gene

Transgenic mice overexpressing the phosphoenolpyruvate carboxykinase/bovine growth hormone (PEPCK/ bGH) hybrid gene and normal (nontransgenic) littermate controls (10 males + 10 females/group) were given access to tapwater and an ascending series of concentrations of ethanol (1.0–22.0%), then a similar ascending series of concentrations of nicotine (1.0–40.0 μg/ml), in a two-bottle choice test. Male transgenic mice consumed more and exhibited greater preferences for ethanol and nicotine than control males; transgenic females consumed less and showed lower preferences for ethanol, but not nicotine, than control females. These results suggest that chronic exposure to high levels of bGH may modulate the rewarding effects of ethanol and nicotine in mice in a gender-specific fashion.     

NMR Investigation of the Futile Cycling of Ethanol in Chronic Alcoholic Rats

Weight gain efficiency differences previously reported between alcohol-fed rats and their controls were investigated. Additionally, the futile cycling of ethanol proposed to explain such differences was studied by NMR spectroscopy. Male Sprague-Dawley rats were fed a nutritionally adequate diet containing 36% of the calories as alcohol, and their paired controls were fed an isocaloric diet for 1 f weeks to establish conditions of chronic alcohol feeding. Normalized metabolic efficiencies varied significantly during the initial 2-week period (6.86 ± 0.51 vs. 2.83 ± 0.18 g/kcal × 10⁻²) for control and alcohol-fed groups, respectively, and to a lesser extent over the entire feeding period (6.41 ± 0.78 vs. 4.60 ± 0.27 g/kcal × 10⁻²) for control and alcohol-fed groups, respectively. Alcohol-induced weight gain inefficiency in metabolism has previously been studied and explained by a variety of different biochemical and physiological mechanisms. One possible pathway of energy wastage may occur due to ethanol futile cycling from ethanol to acetaldehyde through the microsomal ethanol oxidation system pathway, and simultaneously from acetaldehyde to ethanol via the ADH pathway. This futile cycle represents a net loss of 6 ATP/cycle, corresponding to the loss of two reducing equivalents (NADH and NADPH). 1H NMR spectroscopy was used to test for this cycling in blood extracts after administration of 1,1-²H₂ ethanol. No futile cycling was detected either during the initial 2 weeks of feeding or after the entire feeding period.     

盐析法提取卵黄免疫球蛋白的研究

为了确定盐析法提取特异性卵黄免疫球蛋白的最佳盐浓度，采用SDS—PAGE鉴定IgY的纯度，用RID测定IgY含量，间接ELISA法检测特异性卵黄抗体的活性。结果表明：用饱和度50％的硫酸铵盐析一次，再用140g／L的硫酸钠溶液盐析，可以获得469，6的回收率和77％的纯度。盐析液经超滤膜包超滤后制得的冷冻干燥制品，保持了完整的抗体结构和良好的抗体活性。这一结果为IgY的进一步分离纯化奠定了基础。     

Urinary 5-Hydroxytryptophol: A Possible Marker of Recent Alcohol Consumption

Urinary 5-hydroxytryptophol (5-HTOL) is currently being evaluated as a marker of recent alcohol consumption. To compensate for urinary dilution, the molar ratio between 5-HTOL and 5-hydroxyindole-3-acetic acid (5-HIAA) is used. The 5-HTOL/5-HIAA ratio showed a satisfactory degree of individual stability when it was followed in a group of teetotallers for 1 month. The mean value of 5-HTOL/5-HIAA in a group of 69 persons abstaining from alcohol was 7.6 (pmoles 5-HTOL/nmoles 5-HIAA). Ninety-seven percent had values ranging from 4 to 17, with no value exceeding 20. A group of healthy volunteers were tested 12 hr after alcohol consumption and showed a dose-dependent and statistically significant elevation in the 5-HTOL/5-HIAA ratio. Four regular alcohol consumers who were followed during a period of 3 months of drinking had elevated values of the 5-HTOL/5-HIAA ratio in 60% of their urine samples. The present study indicates that urinary 5-HTOL/5-HIAA is a sensitive and reliable marker of recent alcohol consumption. We propose that a 5-HTOL/5-HIAA ratio greater than 20 (pmoles/nmoles) can be used to indicate recent alcohol consumption. This limit gives a low frequency of false positives; the statistical probability of having a value greater than 20 during abstinence from alcohol was calculated to be less than 0.001.     

长期饮酒对大鼠睾丸睾酮合成和雄激素结合蛋白mRNA表达的影响

目的探讨饮酒对大鼠睾丸组织睾酮合成和雄激素结合蛋白（ABP）mRNA表达的影响。方法雄性Wistar大鼠40只，按体重随机分为4组，每组10只，即对照组（蒸馏水5g·kg^-1·d^-1）；大剂量饮酒组（酒精量5g·kg^-1·d^-1）；中剂量饮酒组（酒精量2．5g·kg^-1·d^-1）；小剂量饮酒组（酒精量0．5g·kg^-1·d^-1），喂养时间5个月。ELISA测定睾酮含量，RT—PCR测定睾丸组织外周型苯二氮革受体（PBR）、PPARα和ABP mRNA水平。结果与对照组相比，（1）大剂量饮酒组大鼠睾丸组织睾酮含量下降31．13％（P〈0．05），中剂量饮酒组下降26．8％（P〈0．05），小剂量饮酒组下降14．2％（P〉0．05）；（2）各饮酒组PBR mRNA水平明显降低（均P〈0．05），PPARα mRNA水平也明显降低（均P〈0．05）；（3）各饮酒组ABP mRNA水平明显下降（均P〈0．05）。结论长期饮酒可显著降低大鼠睾酮合成，PBR和PPARα表达降低是其可能机制之一；长期饮酒还可抑制大鼠ABP表达，影响睾酮生物学效应的发挥。     

Diplotypes of the human serotonin 1B receptor promoter predict growth hormone responses to sumatriptan in abstinent alcohol-dependent men.

BACKGROUND: Some studies have associated alcohol dependence (AD) with the human serotonin (5-HT)(1B) receptor (HTR1B). This investigation explored the functional responsivity of HTR1B in abstinent AD men using a sumatriptan challenge, while measuring genetic heterogeneity in the HTR1B promoter. METHODS: Abstinent AD men (n = 27) and abstinent men without any alcohol use disorder (n = 19) were administered 6 mg of sumatriptan succinate, subcutaneously. Plasma samples collected over the following 2 hours were assayed for growth hormone (GH) concentrations. His DNA was genotyped for the A-161T and T-261G polymorphisms of the HTR1B promoter and diplotypes determined. RESULTS: Integrated GH responses were predicted by interactions of AD and promoter diplotypes, as well as subject ethnicity. The final model accounted for nearly 35% of the variance in GH responses. Post hoc evaluation revealed that AD was associated with a blunting of GH secretion only among individuals with the most common HTR1B diplotype (TT/TT). CONCLUSIONS: A blunting of GH responses in abstinent AD men was observed only among those with the most common HTR1B promoter diplotype. Less common promoter diplotypes appeared protective. Controlling for genetic background is a useful augmentation of case-control pharmacological challenge strategies designed to elucidate the psychobiology of AD and other complex disorders.