Daily Ethanol Research Articles

Metabolomic profiling reveals novel biomarkers of alcohol intake and alcohol-induced liver injury in community-dwelling men.

ObjectiveMetabolomics is a promising approach to the identification of biomarkers in plasma. Here, we performed a population-based, cross-sectional study to identify potential biomarkers of alcohol intake and alcohol-induced liver injury by metabolomic profiling using capillary electrophoresis-mass spectrometry (CE-MS).MethodsFasting plasma samples were collected from 896 Japanese men who participated in the baseline survey of the Tsuruoka Metabolomics Cohort Study, and 115 polar metabolites were identified and absolutely quantified by CE-MS. Information on daily ethanol intake was collected through a standardized, self-administered questionnaire. The associations between ethanol intake and plasma concentration of metabolites were examined. Relationships between metabolite concentrations or their ratios and serum liver enzyme levels in the highest ethanol intake group (>46.0 g/day) were then examined by linear regression analysis. Replication analysis was conducted in 193 samples collected from independent population of this cohort.ResultsNineteen metabolites were identified to have an association with daily alcohol consumption both in the original and replication population. Three of these metabolites (threonine, glutamine, and guanidinosuccinate) were found to associate well with elevated levels of serum liver enzymes in the highest ethanol intake group, but not in the non-drinker group. We also found that the glutamate/glutamine ratio had a much stronger relation to serum γ-glutamyltransferase, aspartate transaminase, and alanine transaminase than glutamate or glutamine alone (standardized beta = 0.678, 0.558, 0.498, respectively).ConclusionsWe found 19 metabolites associated with alcohol intake, and three biomarker candidates (threonine, guanidinosuccinate and glutamine) of alcohol-induced liver injury. Glutamate/glutamine ratio might also be good biomarker.Electronic supplementary materialThe online version of this article (doi:10.1007/s12199-015-0494-y) contains supplementary material, which is available to authorized users.

Jodina rhombifolia leaves lyophilized aqueous extract decreases ethanol intake and preference in adolescent male Wistar rats

The leaves of Jodina rhombifolia (Hook. & Arn.) Reissek (Santalaceae) are utilized as anti-alcoholic in Argentine folk medicine. This study was designed to investigate the anti-alcohol properties in adolescent male Wistar rats (postnatal day 29; 83–105g of weight). We utilized the “self-administration model”, which ethanol was offered in the standard home-cage through two-bottle free-choice regimen between an ethanolic solution (20% in tap water, v/v) and tap water with unlimited access for 24h per day for 10 consecutive days. The results obtained show that repeated administration of J. rhombifolia lyophilized extract, markedly reduced ethanol voluntary intake on dose dependent bases. The magnitude in reduction of daily ethanol intake was approximately 29%, 44% and 68%, for the rat groups treated with 62.5, 125 and 250mg/kg of extract, respectively. Ethanol preference (proportion of ethanol intake versus total fluid intake) was significantly reduced: 21.37%±0.79 (0mg/kg); 15.83%±0.93 (62.5mg/kg); 15.22%±1.30 (125mg/kg) and 9.38%±0.57 (250mg/kg). Daily food intake was significantly higher (p<0.05) in the group treated with 250mg/kg of JRLE in comparison with vehicle-dose group; the reduction in ethanol intake was associated with a compensatory increase in food intake, probably because in the control group animals a part of the total caloric intake was supplied by ethanol. Treatment was very well tolerated by all animals and without apparent side-effects. These results contribute to the scientific validation of the antialcoholic indication of this botanic species in Argentine folk medicine.

Safety of daily ethanol locks for urinary catheters in critically ill children: A pilot study

Catheter-associated urinary tract infections represent a significant medical burden in critically ill children. Ethanol locks have been shown to be effective and safe for central line-associated bloodstream infection prevention and we propose utilizing this strategy for urinary catheters. Because this has never been done, we evaluated its safety with a pilot study hypothesizing that ethanol locks in urinary catheters would result in negligible alcohol absorption and negligible irritation of the bladder.

Central catheter-associated bloodstream infection reduction with ethanol lock prophylaxis in pediatric intestinal failure: broadening quality improvement initiatives from hospital to home.

Children with intestinal failure are at high risk for developing central catheter-associated bloodstream infections (CCABSIs) owing to children's chronic dependence on central venous catheters for parenteral nutrition. To evaluate the effectiveness and safety of the addition of ethanol lock prophylaxis to a best-practice CCABSI prevention bundle on hospital and ambulatory CCABSI rates in children with intestinal failure. Quality improvement and statistical process control analysis that took place at a tertiary care pediatric hospital and patient homes. Participants included children who were 18 years or younger with intestinal failure requiring a central venous catheter. Central catheter-associated bloodstream infection prevention bundle that included daily ethanol lock prophylaxis. Central catheter-associated bloodstream infection rates and safety outcomes (central catheter insertions, repairs, and hospitalizations) before (January 1, 2011-January 31, 2012) and after (February 1, 2012-December 31, 2013) ethanol lock prophylaxis bundle implementation. Twenty-four children with intestinal failure received the ethanol lock prophylaxis CCABSI prevention bundle for a median of 266 days (range, 12-635 days). Rates of CCABSI decreased from 6.99 CCABSIs per 1000 catheter days at baseline to 0.42 CCABSI per 1000 catheter days after ethanol lock prophylaxis bundle implementation, despite an increase in the total number of catheter days. A subset of 14 children who received prolonged ethanol lock prophylaxis (≥3 months) had fewer median (range) central catheter insertions 0 (0-2) vs 3 (0-6); P = .001. The pre-ELP intervention CCABSI rates in this subset was 7.01 per 1000 catheter days vs 0.64 per 1000 catheter days for post-ELP intervention (P = .004). There were no significant differences in the total number of hospital admissions; however, there were fewer hospitalizations for fever and CCABSI (P = .003). A best-practice CCABSI prevention bundle that included ethanol lock prophylaxis in both the hospital and home was successfully implemented, well tolerated, and demonstrated a significant and sustained reduction in preventable harm in the form of CCABSIs in children with intestinal failure.

Assessment of affective and somatic signs of ethanol withdrawal in C57BL/6J mice using a short-term ethanol treatment

Alcohol is one of the most prevalent addictive substances in the world. Withdrawal symptoms result from abrupt cessation of alcohol consumption in habitual drinkers. The emergence of both affective and physical symptoms produces a state that promotes relapse. Mice provide a preclinical model that could be used to study alcohol dependence and withdrawal while controlling for both genetic and environmental variables. The use of a liquid ethanol diet offers a reliable method for the induction of alcohol dependence in mice, but this approach is impractical when conducting high-throughput pharmacological screens or when comparing multiple strains of genetically engineered mice. The goal of this study was to compare withdrawal-associated behaviors in mice chronically treated with a liquid ethanol diet vs. mice treated with a short-term ethanol treatment that consisted of daily ethanol injections containing the alcohol dehydrogenase inhibitor, 4-methylpyrazole. Twenty-four hours after ethanol treatment, mice were tested in the open field arena, the elevated plus maze, the marble burying test, or for changes in somatic signs during spontaneous ethanol withdrawal. Anxiety-like and compulsive-like behaviors, as well as physical signs, were all significantly elevated in mice undergoing withdrawal, regardless of the route of ethanol administration. Therefore, a short-term ethanol treatment can be utilized as a screening tool for testing genetic and pharmacological agents before investing in a more time-consuming ethanol treatment.

People with alcohol use disorders in specialized care in eight different European countries.

To provide a description of patients receiving alcohol treatment in eight different European countries, including the level of comorbidities and functional limitations. Drinking behaviours, DSM-IV alcohol use disorder (AUD), mental and somatic comorbidities, disability and health services utilization of 1767 patients from various specialized treatment settings were assessed as representative for regions of eight European countries. Severity of alcohol dependence (AD) in terms of drinking level was compared with a large representative US sample. Patients in specialized care for AUDs showed high levels of consumption [average level of daily ethanol intake: 141.1 g, standard deviation (SD): 116.0 g], comorbidity [e.g. liver problems: 19.6%, 95% confidence interval (CI): 17.5-21.6%; depression: 43.2%, 95% CI: 40.7-45.8%; anxiety: 50.3%, 95% CI: 47.8-52.9%], disability and health services utilization (average number of nights spent in hospital(s) during the last 6 months: 8.8, SD: 19.5 nights). Severity of AD was similar to the US sample, but European men consumed on average more alcohol daily. High levels of consumption, somatic and mental comorbidities, disability and functional losses were found in this representative treatment sample, indicating that treatment was initiated only at severe stages of AUDs. Earlier initiation of treatment could help avoid some of the health and social burden.

Reduction in voluntary ethanol intake following repeated oral administration of Jodina rhombifolia lyophilized aqueous extract in male Wistar rats

Ethnopharmacological relevanceThe leaves of Jodina rhombifolia (Hook. & Arn.) Reissek (SANTALACEAE) is utilized in Argentine folk medicine for the treatment of alcoholism. Aim of the study: To evaluate the antialcoholic activity of Jodina rhombifolia lyophilized aqueous extract (JRLE) in male Wistar rats. Materials and methodsRats were housed individually in standard plastic cages with wood chip bedding. Throughout the duration of experiment, ethanol was offered in the standard home-cage; two-bottle free-choice regimen between an ethanolic solution (20% in tap water, v/v) and tap water with unlimited access for 24h per day for 10 consecutive days. Rats were administrated intragastrically twice daily (1ml/200g) for 10 consecutive days, with the control vehicle (distilled water) or one of the doses of JRLE (125, 250 and 500mg/Kg weight). Body weight, ethanol, water and food intake were measured every day at the same hour during the 10 days of experimentation. ResultsThe reducing effect of JRLE on daily ethanol intake was evidenced from the first day of treatment and persisted throughout the entire treatment period. The treatment did not significantly affect daily water intake neither the body weight gain. Daily food intake was higher in rat groups treated with JRLE. ConclusionThe results obtained in the present preliminary study show that repeated administration of JRLE, markedly reduces ethanol voluntary intake in male Wistar rats. The reduction of consumption was of remarkable magnitude and stable during the treatment 10-days.

Change of cystine/glutamate antiporter expression in ethanol-dependent rats.

Background: Some drugs of abuse down regulate the expression of cystine/glutamate (xCT) antiporter in the nucleus accumbens (Acb) after extinction or withdrawal. The altered level of xCT exchanger in Acb, a structure involved in ethanol reinforcement, may contribute to the pathological glutamatergic signaling, linked to addiction. We hypothesized that the expression of xCT may be changed in Acb and whole brain also in non-dependent (occasional drinkers), ethanol-dependent rats, as well as, during ethanol withdrawal.Methods: Wistar rats were made ethanol-dependent by chronic exposure to an alcoholic milk beverage (from 2.4 to 7.2% v/v ethanol). Ethanol non-dependent rats were exposed to a similar, but non-alcoholic liquid diet and self-administered ethanol (10%) twice a week. Withdrawal in ethanol-dependent rats was studied at 12 h after the last ethanol-enriched diet exposure. Immediately after the measurement of somatic signs of withdrawal, Western blot analysis with a polyclonal antibody against xCT was carried out in a naïve control group, non-dependent and ethanol-dependent rats as well as withdrawal rats, in order to study the level of xCT expression in Acb and whole brain.Results: Non-dependent rats self-administered an average dose of 1.21 ± 0.02 g/kg per session (30 min). Daily ethanol consumption during chronic exposure to the alcoholic beverage ranged from 6.30 ± 0.16 to 13.99 ± 0.66 g/kg. Ethanol dependent rats after suspension of the ethanol-enriched diet have shown significant somatic signs of withdrawal. Western blotting analysis of Acb lysates revealed that xCT was over expressed in ethanol-dependent rats whereas in whole brain preparations xCT was over expressed in both non-dependent and ethanol-dependent rats compared to control group. On the contrary, xCT expression during withdrawal was down regulated in Acb and restored to control level in whole brain preparations.Conclusions: The changes of xCT expression in both Acb and whole brain following ethanol dependence and withdrawal indicate that xCT might represent a novel therapeutic target for the treatment of ethanol addiction.

Semi-quantitative data on ethanol consumption in 354 ET cases and 370 controls

The notion that there is an association between essential tremor (ET) and higher ethanol consumption has crept into the literature; however, the data are limited and conflicted. A total of 354 ET cases and 370 matched controls were enrolled in a clinical-epidemiological study. Average current daily ethanol consumption was estimated using the Willett Semi-quantitative Food Frequency Questionnaire. The proportion of cases and controls who drank any ethanol was similar: 66.7% vs. 64.1%, p=0.46, as was the proportion who reported heavy ethanol consumption: 4.0% vs. 3.5%, p=0.74. The average daily ethanol intake was numerically higher in cases than controls (7.99±12.39 [median=3.03] vs. 6.55±10.62 [median=1.80] g), but this difference did not reach significance (p=0.15). Among cases, there was no correlation between average daily ethanol intake and tremor severity (r=0.008, p=0.88). These data, on more than 700 enrollees, do not support any sizable differences between ET cases and controls in terms of average daily ethanol consumption or ethanol overuse. The absence of a correlation in cases between ethanol consumption and tremor severity goes against the hypothesis that ET patients are self-medicating to a significant degree.

Нитрозирующий стресс и апоптоз нейронов са1-зоны гиппокампа в условиях моделирования хронической алкогольной интоксикации: нейропротективные эффекты тиоцетама

Fulfilled researches showed that modeling of chronic alcohol intoxication by daily intragastric ethanol administration to non-pedigreed male white rats (first 10 days – 15% ethanol solution in dose 4 g/kg, next 10 days – 15% ethanol solution in dose 6 g/kg, then 10 days – 25% ethanol solution in dose 4 g/kg) leads to activation of nitrosorbidi stress reactions and initiation of neuro-apoptosis. Thus, as compared with healthy animals group, in rats’ brain after chronic ethanol administration it was revealed significant increase of nitro-tyrosine (nitrosorbidi stress marker) in cytosolic and mitochondrial fractions of brain homogenate against the background of revealing of apoptosis molecular markers in hippocampal CA1 zone neurons (fragmentation of neuron&amp;#180;s nuclei of hippocampal CA1 zone, increase of density and ratio of apoptotic- and destructive-changed cells) as well as deprivation of anti-apoptotic mechanisms (decrease of density of Bcl-2-positive neurons in hippocampal CA1 zone and decrease of Bcl-2 protein concentration in hippocampus). Subsequent 14-day intragastric administration of complex neuro-metabolic cerebro-protector Thiocetam in dose 100 mg/kg to the animals after chronic alcoholization showed significant protective effect on hippocampal CA1 zone neurons. Thus, Thiocetam administration resulted in decrease of nitrotyrosine levels in mitochondrion and in cytosol of brain of animals with chronic alcoholization as compared with untreated animals and with animals receiving Piracetam. Thiocetam administration to experimental animals led to significant decrease of density of apoptotic- and destructive-changed neurons of hippocampal CA1 zone and ratio of apoptotic-changed cells as compared with control group and animals receiving Piracetam. Course of treatment with Thiocetam increases significantly the density of Bcl-2-positive neurons in CA1 zone of hippocampus and significantly increases concentration of Bcl-2 in brain tissue of experimental animals as compared with control group and animals which received Piracetam according the same schedule. The increase of Bcl-2 protein expression in animals received Thiocetam testifies to the activation of anti-apoptotic defense of damaged neurons under the influence of this preparation. We suppose that one of the molecular mechanisms of neuro-protective effect of Thiocetam in chronic intoxication is the breaking of NO-depended mechanisms of neuro-apoptosis.

The effects of chronic alcohol self-administration on serotonin-1A receptor binding in nonhuman primates

BackgroundPrevious studies have found interrelationships between the serotonin system and alcohol self-administration. The goal of this work was to directly observe in vivo effects of chronic ethanol self-administration on serotonin 5-HT1A receptor binding with [18F]mefway PET neuroimaging in rhesus monkeys. Subjects were first imaged alcohol-naïve and again during chronic ethanol self-administration to quantify changes in 5-HT1A receptor binding. MethodsFourteen rhesus monkey subjects (10.7–12.8 years) underwent baseline [18F]mefway PET scans prior to alcohol exposure. Subjects then drank gradually increasing ethanol doses over four months as an induction period, immediately followed by at least nine months ad libidum ethanol access. A post [18F]mefway PET scan was acquired during the final three months of ad libidum ethanol self-administration. 5-HT1A receptor binding was assayed with binding potential (BPND) using the cerebellum as a reference region. Changes in 5-HT1A binding during chronic ethanol self-administration were examined. Relationships of binding metrics with daily ethanol self-administration were also assessed. ResultsWidespread increases in 5-HT1A binding were observed during chronic ethanol self-administration, independent of the amount of ethanol consumed. A positive correlation between 5-HT1A binding in the raphe nuclei and average daily ethanol self-administration was also observed, indicating that baseline 5-HT1A binding in this region predicted drinking levels. ConclusionsThe increase in 5-HT1A binding levels during chronic ethanol self-administration demonstrates an important modulation of the serotonin system due to chronic alcohol exposure. Furthermore, the correlation between 5-HT1A binding in the raphe nuclei and daily ethanol self-administration indicates a relationship between the serotonin system and alcohol self-administration.

Efficacy of peptide anxiolytic selank during modeling of withdrawal syndrome in rats with stable alcoholic motivation.

We studied the effects of selank on the development of symptoms of acute 48-h alcohol withdrawal in outbred rats drinking 10 % ethanol as the only source of fluid for 24 weeks. In alcohol-preferring animals (mean daily ethanol intake >5.0 g/kg) allowed free choice between 10 % ethanol and water, single intraperitoneal injection of selank in a dose of 0.3 mg/kg eliminated anxiety induced by ethanol withdrawal in tests elevated plus maze and social interaction tests and prevented the formation of mechanical allodynia without affecting ethanol consumption. The fi ndings suggest that selank is effective in eliminating of alcohol withdrawal symptoms in rats.

Effect of sub-chronic intermittent ethanol exposure on spatial learning and ethanol sensitivity in adolescent and adult rats

It has become clear that adolescence is a period of distinct responsiveness to the acute effects of ethanol on learning and other cognitive functions. However, the effects of repeated intermittent ethanol exposure during adolescence on learning and cognition are less well studied, and other effects of repeated ethanol exposure such as withdrawal and chronic tolerance complicate such experiments. Moreover, few studies have compared the effects of repeated ethanol exposure during adolescence and adulthood, and they have yielded mixed outcomes that may be related to methodological differences and/or secondary effects of ethanol on behavioral performance. One emerging question is whether relatively brief intermittent ethanol exposure (i.e., sub-chronic exposure) during adolescence or adulthood might alter learning at a time after exposure when chronic tolerance would be expected, and whether tolerance to the cognitive effects of ethanol might influence the effect of ethanol on learning at that time. To address this, male adolescent and adult rats were pre-treated with sub-chronic daily ethanol (five doses [4.0 g/kg, i.p.] or saline at 24-h intervals, across 5 days). Two days after the last pre-exposure, spatial learning was assessed on 4 consecutive days using the Morris water maze. Half of the animals from each treatment cell received ethanol (2.0 g/kg, i.p.) 30 min prior to each testing session and half of the animals received saline. Ethanol pre-exposure altered water maze performance in adult animals but not in adolescents, and acute ethanol exposure impaired learning in animals of both ages independent of pre-exposure condition. There was no evidence of cognitive tolerance in animals of either age group. These results indicate that a relatively short period of intermittent ethanol exposure during adulthood, but not adolescence, promotes thigmotaxis in the water maze shortly after pre-exposure but does not induce cognitive tolerance to the effects of ethanol in either age group.

Активність інтерферонзалежної 2′,5′-олігоаденілат- синтетази в лімфоїдних клітинах тимуса щурів при сумісній дії етанолу та препарату оцтовокислого цинку

The activity of interferon-induced 2',5'-oligoadenylatesynthetase (2',5'-OA-synthetase) in thymocytes of rats simultaneously treated with ethanol and acetic zinc preparation was studied. The 2',5'-OA-synthetase activity was decreased by 75% after daily ethanol administration for 14 days. The changes were less pronounced at the late terms of the experiment. In vitro stimulation of enzyme activity by inducer cycloferon was more pronounced at the late terms of ethanol action. Combined administration of ethanol and acetic zinc increased the 2',5'-OA-synthetase activity (by 81% at 21th day and by 30% at 28th day) in comparison to the group of animals that consumed ethanol only. The zinc preparation augmented the stimulation of enzyme activity induced by cycloferon, the effect was most prominent at the late terms of the ethanol action (at 28th day). Probably, ethanol depresses the synthesis of interferon or disturbs the functioning of 2',5'-oligoadenylate cascade. The acetic zinc amplifies the interferon synthesis.

Impact of the 2011 Great East Japan Earthquake on the Resumption of Alcohol Consumption After Living-Donor Liver Transplantation for Alcoholic Cirrhosis: A Report of Two Cases

Alcoholic liver disease (ALD) is a leading indication for liver transplantation (LT) in Western countries. The rate of resumption of alcohol abuse is 7% to 95% after LT for ALD. A high prevalence of alcohol abuse has been observed in disaster-exposed populations; however, little is known about the association between resumption of alcohol abuse after LT and disasters. Between June 2007 and March 2011, 3 patients with alcoholic cirrhosis (2 men and 1 woman) underwent living-donor LT (LDLT) at Tohoku University Hospital, Sendai, Japan. The female patient died of graft failure 6 months after LDLT. The other patients (ages 55 and 56 years), who survived to discharge, resumed alcohol abuse after the 2011 Great East Japan Earthquake. Before transplantation, both patients had been abusing alcohol for >35 years, with a daily ethanol intake of 110 g and 140 g, respectively. The period of abstinence from alcohol consumption ranged from 4 to 6 months. After transplantation, patients showed good compliance with treatment and seemed at low risk of relapse until the earthquake. One patient was living in the nuclear evacuation zone at Fukushima, and resumed alcohol consumption after the evacuation. Another patient resumed alcohol consumption while temporarily living apart from his family during restoration work after the disaster. Extreme stress and changes in living arrangements after the Great East Japan Earthquake seemed to trigger the desire to drink. This is the first report on patients who underwent LT for ALD and who resumed alcohol consumption after a disaster.

Adolescent intermittent ethanol exposure diminishes anhedonia during ethanol withdrawal in adulthood

Adolescent alcohol use may interfere with neurodevelopment, increasing the likelihood of adult alcohol use disorders (AUDs). We investigated whether adolescent intermittent ethanol (AIE) exposure alters the adult reward response to ethanol. Adolescent rats were administered ethanol once (moderate exposure; Cohort 1) or three times per day (severe exposure; Cohort 2) in a 2 days on/2 days off pattern. In adulthood, subjects responded for electrical stimulation directed at the posterior lateral hypothalamus in a discrete-trial intracranial self-stimulation (ICSS) procedure that provides current-intensity thresholds as a measure of brain reward function. The effects of ethanol administration and withdrawal were assessed. Control rats showed dose-dependent threshold elevations after acute ethanol, indicating reward deficits. A majority of moderately AIE-exposed rats (Cohort 1) showed threshold lowering after ethanol, suggesting ethanol-induced reward enhancement in this sub-set of rats. Rats exposed to severe AIE (Cohort 2) showed no threshold elevation or lowering, suggesting a blunted affective ethanol response. Daily ethanol induced threshold elevations 24h after administration in control rats but not in either group of AIE-exposed rats, suggesting decreased sensitivity to the negative affective state of ethanol withdrawal. Withdrawal from a 4-day ethanol binge produced robust and enduring threshold elevations in all rats, although threshold elevations were diminished in rats exposed to severe AIE. These results indicate that AIE exposure diminished reward deficits associated with ethanol intoxication and withdrawal and may have increased ethanol-induced reward enhancement in a sub-set of rats. In humans, enhanced ethanol reward accompanied by reduced withdrawal severity may contribute to the development of AUDs.

The effects of age at the onset of drinking to intoxication and chronic ethanol self-administration in male rhesus macaques

Consumption of alcohol begins during late adolescence in a majority of humans, and the greatest drinking occurs at 18-25 years then decreases with age. The present study measured the differences in ethanol intake in relation to age at the onset of ethanol access among nonhuman primates to control for self-selection in humans and isolate age effects on heavy drinking. Male rhesus macaques were assigned first access to ethanol during late adolescence (n = 8), young adulthood (n = 8), or early middle age (n = 11). The monkeys were induced to drink ethanol (4 % w/v in water) in increasing doses (water then 0.5, 1.0, 1.5 g/kg ethanol) using a fixed-time (FT) 300-s schedule of food delivery, followed by 22 h/day concurrent access to ethanol and water for 12 months. Age-matched controls consumed isocaloric maltose-dextrin solution yoked to the late adolescents expected to be rapidly maturing (n = 4). Young adult monkeys had the greatest daily ethanol intake and blood-ethanol concentration (BEC). Only late adolescents escalated their intake (ethanol, not water) during the second compared to the first 6 months of access. On average, plasma testosterone level was consistent with age differences in maturation and tended to increase throughout the experiment more for control than ethanol-drinking adolescent monkeys. Young adulthood in nonhuman primates strongly disposes toward heavy drinking, which is independent of sociocultural factors present in humans. Ethanol drinking to intoxication during the critical period of late adolescence is associated with escalation to heavy drinking.

Early ethanol and water intake: Choice mechanism and total fluid regulation operate in parallel in male alcohol preferring (P) and both Wistar and Sprague Dawley rats

The goal of this study was to clarify similar and distinctly different parameters of fluid intake during early phases of ethanol and water choice drinking in alcohol preferring P-rat vs. non-selected Wistar and Sprague Dawley (SD) rats. Precision information on the drinking amounts and timing is needed to analyze micro-behavioral components of the acquisition of ethanol intake and to enable a search for its causal activity patterns within individual CNS circuits. The experiment followed the standard ethanol-drinking test used in P-rat selective breeding, with access to water, then 10% ethanol (10E) as sole fluids, and next to ethanol/water choice. The novelty of the present approach was to eliminate confounding prandial elevations of fluid intake, by time-separating daily food from fluid access. P-rat higher initial intakes of water and 10E as sole fluids suggest adaptations to ethanol-induced dehydration in P vs. Wistar and SD rats. P-rat starting and overall ethanol intake during the choice period were the highest. The absolute extent of ethanol intake elevation during choice period was greatest in Wistar and their final intake levels approached those of P-rat, contrary to the hypothesis that selection would produce the strongest elevation of ethanol intake. The total daily fluid during ethanol/water choice period was strikingly similar between P, Wistar and SD rats. This supports the hypothesis for a universal system that gauges the overall intake volume by titrating and integrating ethanol and water drinking fluctuations, and indicates a stable daily level of total fluid as a main regulated parameter of fluid intake across the three lines in choice conditions. The present findings indicate that a stable daily level of total fluid comprises an independent physiological limit for daily ethanol intake. Ethanol drinking, in turn, stays under the ceiling of this limit, driven by a parallel mechanism of ethanol/water choice.

Ceftriaxone Treatment Affects the Levels of GLT1 and ENT1 As Well As Ethanol Intake in Alcohol-Preferring Rats

Studies have demonstrated that deletion of equilibrative nucleoside transporter 1 (ENT1) is associated with reduced glutamate transporter 1 (GLT1) level, and consequently increased ethanol intake. In this study, we measured changes in GLT1 and ENT1 levels in prefrontal cortex (PFC), and nucleus accumbens (NAc) core and shell associated with alcohol drinking in alcohol-preferring (P) rats. We examined, then, whether ceftriaxone (CEF) would affect both GLT1 and ENT1 levels in these brain regions. P rats were given 24-h concurrent access to 15 and 30% ethanol, water, and food for 5 weeks. On Week 6, P rats received 100 mg/kg CEF (i.p.) or a saline vehicle for five consecutive days. Ethanol intake was measured daily for 8 days starting on the first day of injections. We found a significant reduction in daily ethanol intake in CEF-treated group, starting on Day 2 of injections. Western blot for GLT1 and binding assay for ENT1 revealed downregulation of GLT1 level, whereas ENT1 levels were increased in the NAc core and NAc shell, respectively, but not in the PFC in saline vehicle group. Importantly, CEF treatment reversed these effects in both NAc core and shell. These findings provide evidence for potential regulatory effects of CEF on both GLT1 and ENT1 expression in reducing ethanol intake.

Transient changes in the endocannabinoid system after acute and chronic ethanol exposure and abstinence in the rat: a combined PET and microdialysis study

Recent biochemical and post-mortem evidence suggests involvement of the endocannabinoid system in alcohol drinking behaviour and dependence. Using [(18)F]MK-9470 small-animal PET imaging, our primary objective was to evaluate in vivo type 1 cannabinoid receptor (CB1R) binding changes in rats subjected to several ethanol conditions: (1) at baseline, (2) after acute intraperitoneal administration of ethanol (4 g/kg) or saline, (3) after 7 days of forced chronic ethanol consumption, and (4) after abstinence for 7 and 14 days. Secondly, levels of anandamide (AEA) in the nucleus accumbens (NAcc) were investigated in the same animals using in vivo microdialysis and correlated with the changes in CB1R binding. In total, 28 male Wistar rats were investigated. Small-animal PET was done on a FOCUS-220 tomograph with [(18)F]MK-9470. Parametric images of [(18)F]MK-9470 binding based on standard uptake values (SUV, as a measure of CB1R binding) were generated. Images were normalized to Paxinos space and analysed voxel-wise using SPM8 (p(height) = 0.005; k(ext) = 200). The AEA content was quantified using HPLC with tandem mass spectrometry detection. Acute ethanol administration increased relative CB1R binding in the NAcc that was positively correlated with the change in AEA levels of that region. In contrast, compared to rats at baseline, AEA levels in the NAcc were not significantly different in rats after chronic ethanol consumption or after a 14-day abstinence period. Chronic ethanol consumption decreased relative CB1R binding in the hippocampus and caudate-putamen, whereas same regions showed increased relative CB1R binding after 7 and 14 days of abstinence compared to the baseline condition. After 7 and 14 days of abstinence, relative CB1R binding additionally decreased in the orbitofrontal cortex. The magnitude of the hippocampal and frontal changes was highly correlated with daily ethanol intake. This study provides in vivo evidence that acute ethanol consumption is associated with enhanced endocannabinoid signalling in the NAcc, indicated by an increased CB1R binding and AEA content. In addition, chronic ethanol exposure leads to regional dysfunctions in CB1R levels, involving the hippocampus and caudate-putamen that are reversible within 2 weeks in this animal model.