EtOH Concentrations Research Articles

Charge-transfer photochemistry of bis(diethyl-diselenocarbamato)copper(II)

The photochemical reactions of bis(diethyl-diselenocarbamato)copper(II), Cu(Et 2dsc) 2, complex have been studied in toluene, CH 2Cl 2, CHCl 3 and chloroalkane/EtOH mixed solvents. Charge-transfer irradiation induces intramolecular oxidation of the ligand and reduction of copper(II) to copper(I) as evidenced by EPR and UV-Vis spectra of the complex as well as quantum yield results. When photolysis is carried out in CHCl 3 or CH 2Cl 2 or in the solvent mixture CHCl 3/EtOH resp. CH 2Cl 2/EtOH of lower than 1:1 EtOH content, the primary photoproduct Cu I(Et 2dsc) is further oxidised in a dark reaction with the chloroalkane producing the corresponding paramagnetic mixed-ligand Cu II(Et 2dsc)Cl complex in equilibrium with its chloride-bridged and EPR silent, dimeric form Cu 2(Et 2dsc) 2Cl 2. At low concentration of EtOH the equilibrium is shifted to the dimeric form whereas at higher than 1:1 EtOH content in the mixed solvent CHCl 3/EtOH it is shifted to Cu II(Et 2dsc)Cl. A reaction mechanism is proposed and the role of ethanol is discussed.

Evidence for the involvement of oxygen free radicals in the ethanol-induced late cellular injury in mouse myeloma cells

In this study, we analysed the ethanol-induced long term cell injury on a general cell model (Sp2/0-Ag14 cell line). Cells were incubated in 1, 5, 10, 15 and 20% of ethanol (EtOH) for 5 min. After washing cell viability was tested by the Trypan Blue exclusion test in 5, 60 min, 4 and 24 h after EtOH exposure. Free radicals were monitored every 30 min by electron spin resonance (ESR) with alpha-phenyl-N-tert-butylnitrone (PBN) spin trapping technique. Scavenger compounds such as glutathione (GSH), dimethyl sulfoxide (DMSO) and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) were applied for 24 h incubation after EtOH exposure. EtOH concentration dependently decreased the cell viability immediately after 5 min exposure, but with 4 and 24 h, a secondary cell destruction was found. Using ESR-spin trapping technique, an increased free radical activity could be detected. DMPO, DMSO and GSH significantly, but in different period protected the cells against free-radical induced cellular damage. EtOH produces an early (immediately after EtOH exposure) and a late (in about 4 h) cellular damage on Sp2/0-Ag14 cells. The oxygen free radicals can be detected in a short time after EtOH exposure, its biological effect manifested as a secondary cell destruction at 4 and 24 h. This phenomenon can be prevented by scavenger compounds.

Lack of Hematologic Effects of Recent Ethanol Ingestion by Trauma Patients

A retrospective investigation was conducted to determine if acute ethanol (EtOH) ingestion before injury leads to hematologic impairment as noted by coagulation and transfusion parameters. Patients older than 18 years of age were grouped according to the presence or absence of detectable EtOH concentrations in the blood, with further subdivision based on an Injury Severity Score of 8 or less or 9 or more. The following direct and indirect indicators of hematologic function were studied: volume of resuscitation fluids administered (including blood products), prothrombin time, partial thromboplastin time, and hematocrit. Of the 304 patients who were evaluated, 152 had detectable EtOH concentrations and 136 had undetectable EtOH concentrations; 16 patients had not been tested for blood EtOH concentrations and were excluded from the analysis. There were no significant differences between groups with regard to blood or fluid requirements or coagulation parameters. Detectable blood EtOH concentrations in trauma patients are not associated with significant changes in transfusion requirements or coagulation parameters compared to patients without detectable EtOH concentrations.

Patterns of Ethanol and Saccharin Intake in P Rats Under Limited-Access Conditions

Patterns of drinking and responding for ethanol (EtOH) and saccharin (SACC) were examined in the alcohol-preferring P rat using various limited-access paradigms. Adult female P rats ( n = 10–20) were given 2-h access to EtOH (10–13% v/v) and SACC (0.0125% g/v) concurrently each day, or each solution individually on alternate days. Total 2-h SACC intake was significantly greater than EtOH under both concurrent (12 ± 2 vs. 7 ± 0.8 ml, p < 0.05) and alternate-day access (18 ± 1.6 vs. 10 ± 0.5 ml) conditions. Under both conditions, however, EtOH intake (over 55% of the total) in the first 15 min was significantly greater than that of SACC (<25% of total). In an operant paradigm, total responding for EtOH (124 ± 29) and SACC (114 ± 7) under 2-h alternate-day conditions did not differ, but 65% of total EtOH responding occurred during the first 20 min versus less than 45% for SACC ( p < 0.05). Increasing response requirements (FR-1 to FR-5) did not significantly alter the total number of EtOH reinforcements, but decreased the total number of SACC reinforcements by approximately 50% ( p < 0.05). Increasing the EtOH concentration from 15% to 35% decreased the number of reinforcements approximately 50% but did not decrease the estimated g/kg EtOH intake. Increasing the SACC concentration from 0.0125% to 0.05%, however, nearly doubled the number of reinforcements. The greater preference for EtOH versus SACC during the initial part of the access period, together with the maintenance of EtOH intake in g/kg when the response requirements and the EtOH concentration were increased, suggests that EtOH intake is motivated by pharmacological consequences. Therefore, different motivational factors appear to underlie EtOH and SACC intake of the P rat. Furthermore, the pattern of EtOH intake and responding displayed by the P rat may be the result of a “bout-” or “binge-” like loss of control under restricted EtOH access conditions.

Ethanol oral self-administration is increased in mutant mice with decreased β-endorphin expression

The relationship between ethanol (EtOH) administration and the endogenous opioid system has been studied for many years and a considerable body of evidence supports the contention that EtOH modulates the production and/or release of endogenous opioid peptides. However, substantially less is known about the converse influence: the effect that opioids have on EtOH sensitivity. In this study, we used the β-endorphin deficient mutant mouse line C57BL/6- Pomc1 tm1Low to investigate the possible role of a specific opioid peptide on EtOH consumption. Homozygous knockout mice (entirely lacking β-endorphin), heterozygous mice (50% β-endorphin expression) and sibling wildtype mice from the same strain were evaluated in a two-bottle free choice paradigm for oral self-administration of EtOH. Across varying EtOH concentrations only the heterozygous mice were found to consistently drink more than wildtype mice. These data support the hypothesis that β-endorphin modulates the response to EtOH.

Peach fruit ripening and quality in relation to picking time, and hypoxic and high CO2 short-term postharvest treatments

Peach fruits (Prunus persica L. Batsch, cv Springcrest) were harvested at two ripening stages (flesh firmness of 60 N, first harvest, and 45 N, second harvest) and maintained at 20°C in air (control) or for 24 and 48 h in streams of ultra low (<1%) oxygen (ULO) or high (30%) CO2 concentration and then transferred to air for up to 8 days. The decline in flesh firmness was strongly reduced by ULO and CO2 treatments in fruits of both harvests, although the effect was stronger in fruits picked earlier in which ethylene biosynthesis remained at the basal level. In fruits of the second harvest, endo β-1,4-glucanase (EGase) activity was lower in ULO- and CO2-treated fruits than in control fruits at the end of the 24 h treatment and the following two days in air. Acetaldehyde (AA) gradually accumulated in control fruit and the highest concentrations were detected during late ripening. Both treatments induced a strong accumulation of AA but, with the exception of the 24 and 48 h CO2 treatments performed on fruits of the second harvest, a decrease in AA content was observed when the fruits were transferred to air. A slight increase in ethanol (EtOH) was found throughout the ripening process in control fruits; ULO and CO2 strongly stimulated EtOH production. When fruits were transferred to air, EtOH concentration declined rapidly. Alcohol dehydrogenase (ADH) activity significantly increased in control fruit only in the late stages of ripening. Greater ADH activity was found throughout the experimental period in fruits of the first harvest treated for 24 h in ULO and CO2, whereas, at day 8, control and treated fruits of the second harvest showed similar ADH activity values. Hypoxic and, to a lesser extent, CO2-enriched atmospheres stimulated Adh gene expression.

Influence of ethanol on the thickness and free energy of film formation of DMPC foam films

Foam films prepared from 1,2-dimirystoil-sn-glycero-3-phosphorylcholine (DMPC) dispersions in water–ethanol mixtures were investigated. Their thickness and contact angle (foam film/meniscus) were measured. Experimental results show that an increase of EtOH concentration in the film forming dispersions leads to a decrease in the film thickness. At EtOH concentrations above 40% v/v the foam films have a bilayer structure without any noticeable core of solvent. The film thickness remains constant with the further increasing of the EtOH concentration up until 50% v/v. This behaviour is corroborated by the strong increase in the contact angles (a decrease in the free energy of film formation) with increasing EtOH concentration. Ellipsometric measurements on the thickness of adsorbed DMPC monolayers and surface pressure isotherms of DMPC spread on the water–ethanol subphases show that the effective area per lipid molecule decreases, resulting in a larger monolayer thickness, when the EtOH concentration in the subphase is increased. An increase of the EtOH concentration leads to a dehydration of the DMPC molecules and a reduction in strength and range of the repulsive hydration force between the film monolayers. The film thickness and the free energy of film formation are governed by the balance of the van der Waals attraction and the repulsive hydration force between the foam film surfaces.

Ethanol Inhibits Lung Clearance of Pseudomonas aeruginosa by a Neutrophil and Nitric Oxide‐Dependent Mechanism, In Vivo

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen that can be found in individuals in which the immune system has been suppressed by HIV/AIDS or chronic alcoholism. We evaluated the role of inducible nitric oxide synthase (NOS II) as a modulator of lung concentrations of P. aeruginosa in normal rats and rats given a single dose of ethanol (ETOH). Rats were pretreated with either sterile saline (PBS, 0.1 ml/kg, i.v.) or the NOS II inhibitor L-N6-iminoethyl lysine (LNIL, 10 mg/kg, i.v.) 15 min before intraperitoneal administration of either PBS (4.5 ml/kg) or ETOH (4.5 g/kg). Thirty min after administration of PBS or ETOH the rats were placed in inhalation chambers and exposed to 45 min of an aerosol containing P. aeruginosa (5 x 10(4) colony forming units, CFU). A group of rats (n = 5-6/treatment/time period) were killed immediately (0 hr) or 4 hr after inhalation of P. aeruginosa. The lungs were homogenized and the P. aeruginosa were grown in nutrient broth to determine the number of viable CFU remaining in the lung. The NOS II and TNFalpha mRNA and protein content lung alveolar macrophages (AM) and neutrophils (PMN) were measured with RT-PCR and Western blot. The concentration of nitrate and nitrite anion in the bronchoalveolar lavage fluid (BALf) and ex vivo incubates of PMN were also measured. The CFU of P. aeruginosa present in the lungs of the four groups of rats at 0 hr did not differ. The CFU of P. aeruginosa in the lung increased (p < 0.05) in rats pretreated with ETOH when compared with that obtained from rats pretreated with PBS. However, pretreatment of rats with LNIL decreased (p < 0.05) the 4 hr lung content of P. aeruginosa. Coadministration of LNIL and ETOH to rats augmented the CFU of P. aeruginosa in lungs to amounts which did not differ from that of rats pretreated with ETOH. Inhalation of P. aeruginosa increased NOS II mRNA and protein in rat AM and PMN. Pretreatment of rats with ETOH alone, or in combination with LNIL, inhibited P. aeruginosa-induced NOS II transcription and translation and AM and PMN nitrate and nitrite generation whereas pretreatment with LNIL alone only inhibited nitrate and nitrite generation. Pretreatment of rats with ETOH suppressed P. aeruginosa stimulated PMN recruitment into the lung whereas LNIL enhanced (p < 0.05) P. aeruginosa-stimulated PMN recruitment into the lung. ETOH-induced increases of the lung content of P. aeruginosa were associated with increased PKC delta isozyme in the membrane of the PMN but could not be explained by altered plasma concentrations of hydrocortisone or ETOH. The data demonstrate that selective inhibition of NOS II-derived NO by LNIL decreases the lung content of P. aeruginosa whereas ETOH inhibits the lung clearance of P. aeruginosa. Speculatively, the difference between these effects of LNIL and ETOH may result from differences in drug-induced changes in lung recruitment of PMN.

Effects of calcium channel blockade on intravenous self-administration of ethanol in rats

In the present study the involvement of voltage-operated calcium channels (VOCCs) in the acquisition and maintenance of operant i.v. ethanol (EtOH) self-administration was investigated in rats. Rats readily learned to self-administer EtOH (unit dose range: 0.5–4% v/v) within five daily 2-h sessions, when infusions were made contingent upon nose-poking in a hole containing infrared sensors. Response rate was related to the EtOH concentration in an inverted U-shaped manner, the maximal rate and intake being observed at a unit dose of 1% v/v (0.27 mg EtOH/infusion). Self-administration of EtOH appeared to be behaviorally specific, as responding in the reinforced hole did not coincide with increased responding in a nonreinforced hole. Daily treatment with the dihydropyridine VOCC blocker nimodipine (2.5–20 mg/kg, i.p., t-15 min) dose-dependently attenuated acquisition of EtOH self-administration; the 5 mg/kg dose resulting in a partial, and the 10 and 20 mg/kg doses in a complete prevention of i.v. self-administration behavior. The effects of nimodipine (2.5–5.0 mg/kg) were considered to be relatively specific, as an inhibition of the reinforced responding could be demonstrated in the absence of a significant effect on nonreinforced responding. When tested in rats showing stable self-administration behavior (unit dose: 1% v/v EtOH), nimodipine showed biphasic dose–response effects; with 2.5 and 5 mg/kg resulting in a mild increase, and 10 and 20 mg/kg resulting in a decrease of self-administration behavior, respectively. The present study suggests that blockade of VOCCs attenuates the reinforcing stimulus effects of EtOH; and, as such, the data may offer an explanation for the previously reported EtOH intake-reducing effects of dihydropyridine calcium channel ligands obtained in two-bottle choice paradigms. Dihydropyridine derivatives, such as nimodipine, may therefore offer an interesting approach to the pharmacotherapy of alcoholism.

Polaprezinc protects gastric mucosal cells from noxious agents through antioxidant properties in vitro.

Polaprezinc has been shown to exert an anti-oxidant property in a tube experiment, protect gastric mucosa from experimental ulcerations in vivo, and accelerate the healing of gastric ulcer in humans. To examine a possible protective effect of polaprezinc on oxidant-mediated injury in primary monolayer cultures of rat gastric fundic mucosa. Cytotoxicity was quantified by measuring 51Cr release. Whether or not polaprezinc exerts an antioxidant property was investigated by determining the effect of this agent on hydrogen peroxide (H2O2)-induced injury. The effects of polaprezinc on superoxide (O2-. ) generation as well as on ethanol (EtOH)-induced injury were also examined. Generation of O2-. was assessed by the reduction in cytochrome c. H2O2 caused a time- and dose-dependent increase in 51Cr release. The dose-response curve of 51Cr release by H2O2 shifted to the right in the presence of polaprezinc. Polaprezinc, at submillimolar concentrations, prevented H2O2-induced 51Cr release. EtOH also caused a dose-dependent increase in 51Cr release, which was prevented by the addition of polaprezinc. The incubation of cells with EtOH caused an increase in cytochrome c reduction, as the concentrations of EtOH increased. Polaprezinc inhibited EtOH-induced cytochrome c reduction. Protection by polaprezinc was microscopically associated with the prevention of monolayer disruption. Polaprezinc is antioxidative and directly protects gastric mucosal cells from noxious agents through its antioxidant properties in vitro. This finding may provide the theoretical basis for the usage of an antiulcer drug with antioxidant properties for the treatment of gastric inflammation, such as that induced by ethanol.

Prostaglandins protect human intestinal cells against ethanol injury by stabilizing microtubules: role of protein kinase C and enhanced calcium efflux.

Prostaglandins (PG) protect gastrointestinal cells against damage induced by ethanol (EtOH) and other noxious agents, a process termed cytoprotection. The present study investigated the relationships between microtubule (MT) stability, protein kinase C (PKC) activation, and calcium efflux as a possible mechanism of PG's protective action using a human colonic cell line (Caco-2) exposed to known damaging concentrations of EtOH (7.5% and 10%). Preincubation of Caco-2 cells with 16,16-dimethyl-PGE2 (PG, 2.6 microM) significantly increased PKC activity in these cells. Pretreatment of Caco-2 cells with 50 microM OAG (a synthetic diacylglycerol and PKC activator) or 30 nM TPA (a direct PKC activator) prior to exposure to 7.5% or 10% EtOH for 5 min significantly reduced cell injury, as determined by trypan blue exclusion, and increased MT stability, as confirmed by confocal microscopy. Pretreatment of Caco-2 cells with 4 alpha-PDD (an inactive phorbol ester, 20 nM) failed to prevent cell injury and disruption of the MT cytoskeleton. Preincubation with staurosporine (a PKC inhibitor, 3 nM) abolished the protective effects of PG in cells exposed to 7.5% and 10% EtOH. Incubation of Caco-2 cells with A23187 (a Ca2+ ionophore), similar to 10% EtOH, caused a significant reduction in cell viability and MT stability. Preincubation with A23187 in combination with PG or OAG prior to subsequent exposure to EtOH significantly abolished the protective effects of PG or OAG pretreatment. Finally, pretreatment with OAG, TPA, or PG resulted in significant increases in calcium-45 efflux, which correlated with increased stability of the MT cytoskeleton. These data suggest that PG possesses direct protective effects against EtOH injury in Caco-2 cells and may act by stabilizing MT through the PKC signal transduction pathway and/or stimulation of calcium efflux from the cells.

VLDL-triglyceride production after alcohol ingestion, studied using [2-13C1] glycerol

We used [2-13C1]glycerol to characterize very low density lipoprotein (VLDL)-triglyceride kinetics and intrahepatic glycerol metabolism in normal men (n = 4) after alcohol (EtOH) ingestion. [2-13C1]glycerol was infused before and after the consumption of 48 g EtOH or a placebo. Three additional subjects also received [1-13C1]acetate in addition to the [2-13C1]glycerol with EtOH treatment. Incorporation of tracer into the glycerol or fatty acid moiety of VLDL-triglyceride was measured by gas chromatography-mass spectrometry and used to calculate VLDL-triglyceride production rates. Intrahepatic triose-phosphate enrichments were also calculated based on mass isotopomer distribution analysis of plasma glucose. There was no difference in VLDL-triglyceride production rates after 48 g EtOH (11.9 +/- 3.7 mg/kg/h) or placebo (14.7 +/- 3. 3 mg/kg/h). The VLDL-triglyceride rate constants calculated by kinetic modeling using the glycerol and acetate tracers in the combined isotope infusion subjects were very closely correlated (r 2 = 0.94). The peak VLDL-glycerol enrichments after EtOH were 22.5 +/- 3.3% versus 7.6 +/- 0.8% after placebo (P < 0.001), while intrahepatic triose-phosphate enrichments were 19.8 +/- 1.3% and 13. 1 +/- 1.2% (P < 0.001), respectively. Moreover, the calculated asymptotic VLDL-glycerol enrichments (representing the hepatic alpha-glycerol phosphate enrichment) were significantly higher after EtOH than placebo. The higher ratio of VLDL-glycerol to triose-phosphate labeling after EtOH suggests a metabolic block at glycerol 3-phosphate dehydrogenase. We conclude that consumption of 48 g EtOH does not increase VLDL-triglyceride production in normal men but does cause accumulation of tracer in hepatic alpha-glycerol phosphate.

Buprenorphine alters ethanol self-administration in rats: dose-response and time-dependent effects.

Buprenorphine is a partial opioid agonist derived from thebaine and has high affinity for mu and kappa opioid receptors. The present study investigated dose-response (0.03, 0.15, 0.3, 3 mg/kg) and time-dependent effects of buprenorphine (1.5 or 4 h post-treatment) on EtOH self-administration in outbred Sprague-Dawley rats. Freely feeding and drinking rats were trained to initiate EtOH self-administration for 1 h daily using the ascending concentration procedure, wherein they were provided with increasing concentrations of EtOH at 2, 5, 7, 9 and 11% (v/v), respectively. Water was concurrently available with each concentration. Animals were maintained on a given concentration of EtOH for 5 days. By day 21, animals began their stabilization on the 11% regimen and remained on this concentration throughout the remainder of the study. EtOH and water consumption were recorded daily at both 10- and 60-min intervals. At 1.5 h post-buprenorphine, all test doses greatly suppressed both EtOH and water intake at the 10-min interval. At the 60-min interval, all but the lowest dose (0.03 mg/kg) significantly suppressed EtOH intake, while only the highest dose (3 mg/kg) suppressed water intake. In contrast to the suppressant profile observed at 1.5 h post-buprenorphine, at 4 h post-buprenorphine the lower doses (0.03 and 0.15 mg/kg) significantly increased EtOH intake while the higher doses (0.3 and 3 mg/kg) continued to suppress intake. None of the doses of buprenorphine altered water intake 4 h post-buprenorphine. The results support previous research demonstrating the utility of low doses of buprenorphine in suppressing behavior rewarded by a non-opioid drug.

Behavioral Detection of Low Concentrations of Ethanol in Milk in the Preweanling Rat

Previous animal models testing infantile reactivity to ethanol (EtOH) in maternal milk used EtOH doses that vastly exceeded levels actually encountered in a mildly or moderately intoxicated dam. The present study assessed whether 12- and 16-day-old rats are capable of detecting EtOH in milk at levels actually recorded in an intoxicated dam. Experiment 1 determined representative levels of EtOH in maternal milk as a function of maternal intragastric administration of EtOH (0.5–3.0 g/kg). Experiment 2A assessed generalization of conditioned taste aversions accrued with a high level of EtOH (6%) in either water or milk vehicles towards lower, more representative EtOH levels obtained from Experiment 1. With body weight gain as the dependent measure, conditioned aversions to milk were evident with the milk vehicle, but there was no detection of EtOH at any level at either age. Detection of the high level of EtOH (6%) in milk, however, was observed by 16 day olds within an habituation paradigm (Exp. 2b) via cardiac and behavioral (locomotion, mouthing) indexes. In Experiment 3 application of Experiment 2’s more sensitive, behavioral index to assess generalization of the conditioned taste aversions revealed detection of a lower, more representative concentration of EtOH (175 mg%) in milk in 16-day-old rats. Overall the results show that the unweaned rat is capable of detecting very low concentrations of EtOH in milk and can modify their behavior accordingly. The expression of this capability is not, however, homogenous across different response indexes. In conjunction with prior research it is clear that the infant rat’s perception of EtOH in milk, including the very low levels of EtOH found in maternal milk during mild or moderate intoxication, is a relevant experience for generating new responses towards EtOH.

An exported inducer peptide regulates bacteriocin production in Enterococcus faecium CTC492.

Production of the bacteriocins enterocin A and enterocin B in Enterococcus faecium CTC492 was dependent on the presence of an extracellular peptide produced by the strain itself. This induction factor (EntF) was purified, and amino acid sequencing combined with DNA sequencing of the corresponding gene identified it as a peptide of 25 amino acids. The gene encodes a prepeptide of 41 amino acids, including a 16-amino-acid leader peptide of the double-glycine type. Environmental factors influenced the level of bacteriocin production in E. faecium CTC492. The optimal pH for bacteriocin production was 6.2. At pH 5.5, growth was slow, and very little bacteriocin was formed. The presence of NaCl or ethanol (EtOH) was also inhibitory to bacteriocin production, and at high concentrations of these solutes, no bacteriocin production was observed. The induction factor induced its own synthesis, and by dilution of the culture 106 times or more, nonproducing cultures were obtained. Bacteriocin production was induced in these cultures by addition of EntF. The response was linear, and low bacteriocin production could be induced by about 10(-17) M EntF. This response was attenuated by low pH or the presence of high concentrations of NaCl or EtOH, and 300 times more EntF was needed to induce detectable bacteriocin production in the presence of 6.5% NaCl. High levels of bacteriocin production in cultures grown at low pH or in the presence of high concentrations of NaCl or EtOH were obtained by addition of sufficient amounts of EntF.

Voluntary Ethanol Consumption in Male Adolescent Hamsters Increases Testosterone and Aggression

The immediate and long-term biologic and behavioral consequences of voluntary ethanol (EtOH) exposure during male adolescence are unknown. In the present study, male golden hamsters voluntarily drank from a 15% EtOH solution in addition to consuming dry laboratory chow and water ad lib from Postnatal Day 25 to Postnatal Day 43. Over this adolescent period, they drank an average of 13 g/kg/day of EtOH, resulting in a mean blood EtOH concentration of ca. 53 mg %. On Postnatal Day 35, a period of enhanced sensitization and activation of the gonadal axis, testosterone levels were twice as high in EtOH animals than in sucrose-yoked controls. However, this difference disappeared by Postnatal Day 53, as EtOH and control animals showed comparable adult levels of plasma testosterone. When tested for aggression several days after the cessation of EtOH exposure, hamsters showed enhanced attack behavior toward smaller intruders placed into their home cage. These results suggest that voluntary EtOH exposure during male adolescence has specific neuroendocrine effects with lasting behavioral consequences.

Clinically relevant concentrations of ethanol attenuate primed neutrophil bactericidal activity.

Acute alcohol intoxication is associated with an increased risk of infection in the injured patient. The impact of clinically relevant levels of ethanol (ETOH) on neutrophil (PMN) bactericidal activity remains ill-defined. PMN priming optimizes microbicidal activity by enhancing oxygen radical production, degranulation, and adhesion molecule up-regulation. We hypothesized that clinically relevant levels of ETOH attenuate these primed PMN responses critical to eradicate infection. After incubation with ETOH (0-1.0%), isolated human PMNs were primed with beta-acetyl-gamma-O-alkyl and activated with N-formyl-methionyl-leucyl-phenylalanine. Superoxide generation was measured by cytochrome c reduction, elastase release was measured by cleavage of methoxysuccinyl-ala-ala-pro-val-p-nitroanilide, and CD11b was measured by fluorescent monoclonal antibody staining. Bactericidal activity was assessed by Staphylococcus aureus killing. ETOH attenuated superoxide production dose-dependently with significance at 0.3% ETOH. Elastase release was attenuated starting at 0.2% ETOH, and CD11b expression was reduced starting at 0.4% ETOH. S. aureus killing was impaired dose-dependently with significance at 0.3% ETOH. Clinically relevant concentrations of ETOH attenuate PMN functions critical in host defense against invading pathogens. These results provide direct in vitro evidence consistent with previous in vivo data that acute alcohol intoxication is important in the pathogenesis of trauma-related infections.

Protection against ethanol injury by prostaglandin in a human intestinal cell line: role of microtubules.

Prostaglandins have been shown to protect the gastrointestinal (GI) epithelium from injury induced by various luminal insults independent of their known acid-inhibitory effects, a process termed "cytoprotection." The mechanism of this protective action remains unknown. The present investigation determined the role of microtubules (a major cytoskeletal component) in GI injury induced by ethanol (EtOH) and its prevention by 16,16-dimethylprostaglandin E2 (dmPGE2) using cells from a human colonic cell line known as Caco-2 cells. These cells were preincubated in Eagle's minimum essential medium with and without dmPGE2 (2.6 microM) for 15 min and subsequently incubated in media containing 1, 2.5, 5, 7.5, and 10% EtOH. The effects on cell viability and tubulin (the major protein backbone of microtubules) were then determined. EtOH concentrations > or = 2.5% extensively disrupted the microtubules as demonstrated by fragmentation, kinking, and perturbation of the microtubule organizer center. EtOH treatment also led to a significant decrease in the S2 (polymerized) fraction and an increase in the S1 (monomeric) pool of tubulin. Concomitant with these effects were marked decreases in cellular viability. DmPGE2 pretreatment abolished the disruption of microtubules, significantly increased the S2 fraction of tubulin, and increased cellular viability in cultures exposed to EtOH. Furthermore, pretreatment with colchicine, an inhibitor of microtubule assembly, prevented the cytoprotective action of dmPGE2. Taxol, a microtubule stabilizing agent, mimicked the effects of dmPGE2 by also enhancing microtubule integrity and increasing cellular viability in cells exposed to EtOH. Our data indicate that organization and stabilization of microtubules may play an essential role in the mechanism of prostaglandin-induced protection.

Ethanol sensitivity and subunit composition of NMDA receptors in cultured striatal neurons

Assessment of ethanol (EtOH) sensitivity was combined with analysis of N -methyl- d-aspartate (NMDA) NR1-NR2 subunit composition in primary cultured striatal neurons. Subunit composition was determined by western blot analysis; assessment of ifenprodil and spermine sensitivity during whole-cell patch-clamp recordings. From 3–21 days in culture, NR2B was the only NR2 subunit detected using NR2 subunit specific antibodies; NMDA-induced currents were strongly inhibited by the NR2B-selective antagonist ifenprodil. Two populations of neurons were identified at all ages in culture: those in which NMDA-induced current was or was not potentiated by 100 μM spermine. This suggested that the striatal neurons expressed functional NMDARs which lacked or contained the NR1 N-terminal cassette. The EtOH sensitivity did not differ between these two populations of neurons nor did it change with age in culture at all concentrations of EtOH studied. Human embryonic kidney (HEK) 293 cells containing NR1-1a or NR1-1b with either the NR2A or NR2B subunits did not differ in their EtOH sensitivity. Thus, it would appear that the presence or absence of the N-terminal cassette does not affect the EtOH sensitivity of recombinant NMDARs and native NMDARs expressed in cultured striatal neurons.

Combination of Hot Water and Ethanol to Control Postharvest Decay of Peaches and Nectarines

Spores of Monilinia fructicola or Rhizopus stolonifer were immersed in water or 10% ethanol (EtOH) for 1, 2, 4, or 8 min at temperatures of 46 or 50°C to determine exposure times that would produce 95% lethality (LT95). EtOH reduced the LT95 by about 90%. Peaches and nectarines infected with M. fructicola were immersed in hot water alone or with EtOH to control decay. EtOH significantly increased the control of brown rot compared to water alone. Immersion of fruit in water at 46 or 50°C for 2.5 min reduced the incidence of decayed fruit from 82.8% to 59.3 and 38.8%, respectively. Immersion of fruit in 10% ethanol at 46 or 50°C for 2.5 min further reduced decay to 33.8 and 24.5%, respectively. Decay after triforine (1,000 μg ml-1) treatment was 32.8%. Two treatments, 10% EtOH at 50°C for 2.5 min and 20% EtOH at 46°C for 1.25 min, were selected for extensive evaluation. The flesh of EtOH-treated fruit was significantly firmer, approximately 4.4 N force, than that of control fruit among seven of nine cultivars evaluated. No other factor evaluated was significantly influenced by heated EtOH treatments. The EtOH content of fruit treated with 10 or 20% EtOH was approximately 520 and 100 μg g-1 1 day and 14 days after treatment, respectively.