Single Dose Of Ethanol Research Articles

Maternal Alcohol Consumption Increases Sphingosine Levels in the Brains of Progeny Mice

The effect of 'binge' alcohol upon sphingolipid metabolism in the fetal alcohol syndrome (FAS) was examined in pregnant mice (C57BL/6J) by administering a single dose of alcohol during the third trimester (gestational day 15-16). The control mice were administered a sucrose solution of equal caloric value. Brains from progeny at postnatal days 5, 15, 21 and 30 were dissected into three regions, and sphingolipid concentrations of the brain regions were determined including assay of monoglycosylceramide, ceramide, sphingosine and sphingomyelin. We found that a single dose of ethanol induces an elevation of sphingosine (2-3.5-fold) in the brain of progeny. The level of brain ceramide at a dose of 1.5 g/kg was significantly higher than control. Alcohol consumption during pregnancy induces neuronal loss in progeny brains. Our result suggests that the elevation of sphingosine in progeny brain induced by maternal alcohol consumption may be responsible for observed neuronal loss in FAS.

Acetaldehyde accumulation in rat mammary tissue after an acute treatment with alcohol

Previous studies reported the presence in rat mammary tissue of a cytosolic xanthine oxidoreductase pathway for the metabolism of alcohol to acetaldehyde and hydroxyl radicals and to the microsomal biotransformation of ethanol to acetaldehyde. It was also reported that after chronic ethanol drinking stressful oxidative conditions can be observed. The present work reports that even after single doses of ethanol, given at three different levels (6.3 g kg(-1); 3.8 g kg(-1) or 0.6 g kg(-1) p.o.), acetaldehyde accumulates for prolonged periods of time in the mammary tissue to reach concentrations higher than in blood (e.g. 5.1+/-1.2 nmol g(-1) versus 0.2+/-0.1 nmol ml(-1), for 6.3 g kg(-1) dose, 6 h after intoxication). The presence in rat mammary tissue of low activities of additional enzymes able to generate acetaldehyde was established (alcohol dehydrogenase: 0.97+/-0.84 mU mg(-1) protein; CYP2E1: 1.30+/-0.12 x 10(-2) pmol 4-nitrocatechol min(-1) mg(-1) protein) and a low activity of aldehyde dehydrogenase was observed in the cytosolic, mitochondrial and microsomal fractions (0.02+/-0.04; 0.35+/-0.09 and 0.72+/-0.19 mU mg(-1) protein, respectively). After a single high dose of ethanol, an increased susceptibility to oxidative stress was observed, as evidenced by changes in the shape of t-butylhydroperoxide induced emission of chemiluminescence in mammary tissue (6.3 g kg(-1) dose; at 3 and 6 h). In summary, the results show that even after single doses of ethanol, acetaldehyde, either formed in situ or arriving via blood, tends to accumulate in mammary tissue and that this condition might decrease cell defenses against injury.

Matrix Proteolytic Activity During Wound Healing: Modulation by Acute Ethanol Exposure

Clinical studies demonstrate that intoxicated patients exhibit an increased incidence of wound healing complications. Previous studies in a murine excisional wound model revealed that acute ethanol exposure impairs the wound healing response, causing decreased angiogenesis and a significant reduction in wound collagen content. Using the same murine model of excisional wounding, we examined the effect of a single dose of ethanol on the overall collagen content and collagen type I and type III mRNA expression, transforming growth factor-beta (TGF-beta) production, and levels of several components of the extracellular matrix proteolytic cascade. Wounds from ethanol-treated mice exhibited a significant decrease in collagen and in the production of collagen type I mRNA compared with saline controls. Exposure to ethanol also caused significant increase in wound TGF-beta by day 2 after injury (1.69 +/- 0.29 vs 12.34 +/- 3.97 pg/microg protein, p<0.01). In addition, wounds from mice exposed to ethanol had significantly increased levels of active urokinase plasminogen activator at day 7, (205.10 +/- 48.79 vs 642.70 +/- 159.80 pg/microg protein, p<0.001). The level of matrix metalloproteinase-8, a collagen type I proteinase, was 2.2-fold higher in wounds of ethanol-treated mice compared with control at day 7 (p<0.05). These studies demonstrate that a single dose of ethanol decreases collagen production, increases the production of TGF-beta and increases levels of matrix degrading enzymes. This alteration in protease balance may partially explain the impaired wound healing that follows acute alcohol intoxication.

Biochemical and ultrastructural alterations in the rat ventral prostate due to repetitive alcohol drinking

Previous studies showed that cytosolic and microsomal fractions from rat ventral prostate are able to biotransform ethanol to acetaldehyde and 1-hydroxyethyl radicals via xanthine oxidase and a non P450 dependent pathway respectively. Sprague Dawley male rats were fed with a Lieber and De Carli diet containing ethanol for 28 days and compared against adequately pair-fed controls. Prostate microsomal fractions were found to exhibit CYP2E1-mediated hydroxylase activity significantly lower than in the liver and it was induced by repetitive ethanol drinking. Ethanol drinking led to an increased susceptibility of prostatic lipids to oxidation, as detected by t-butylhydroperoxide-promoted chemiluminiscence emission and increased levels of lipid hydroperoxides (xylenol orange method). Ultrastructural alterations in the epithelial cells were observed. They consisted of marked condensation of chromatin around the perinuclear membrane, moderate dilatation of the endoplasmic reticulum and an increased number of epithelial cells undergoing apoptosis. The prostatic alcohol dehydrogenase activity of the stock rats was 4.84 times lower than that in the liver and aldehyde dehydrogenase activity in their microsomal, cytosolic and mitochondrial fractions was either not detectable or significantly less intense than in the liver. A single dose of ethanol led to significant acetaldehyde accumulation in the prostate. The results suggest that acetaldehyde accumulation in prostate tissue might result from both acetaldehyde produced in situ but also because of its low aldehyde dehydrogenase activity and its poor ability to metabolize acetaldehyde arriving via the blood. Acetaldehyde, 1-hydroxyethyl radical and the oxidative stress produced may lead to epithelial cell injury.

Lack of aldehyde dehydrogenase ameliorates oxidative stress induced by single-dose ethanol administration in mouse liver

Polymorphism of aldehyde dehydrogenase 2 (ALDH2), denoted ALDH2*2, is far more common in East Asian countries. Acetaldehyde, an intermediate metabolite of ethanol, is metabolized very slowly in people who have ALDH2*2, as the mutated ALDH2 lacks acetaldehyde metabolizing activity. On the other hand, it is well established that metabolism of ethanol causes oxidative stress in liver tissue. To examine the consequences of this polymorphism on ethanol-induced oxidative stress in liver tissue, we conducted a study using Aldh2 knockout mice. Aldh2+/+ and Aldh2−/− mice were orally administered ethanol at a dose of 5g/kg body weight. Levels of malondialdehyde, an indicator of oxidative stress, and glutathione, a key antioxidant, in liver tissue were analyzed 0–24h after administration. Levels of malondialdehyde were significantly lower in Aldh2−/− mice than in Aldh2+/+ mice at 12h after injection, while levels of glutathione were higher in Aldh2−/− mice than in Aldh2+/+ mice at 6 and 12h after injection. Our results suggest that a lack of ALDH ameliorates ethanol-induced oxidative stress in liver tissue.

Teratogenic Effects of the Interaction Acetylsalicylic Acid (ASA) and Ethanol: Morphologic and Morphometric Evaluation of the Lingual Epithelium in Rat Fetuses

The objective of the present work was to evaluate the teratogenic effects of the interaction between acetylsalicylic acid (ASA) and ethanol on the epithelium of the lingual mucosa in rat fetuses. On the 10th pregnancy day, a single intraperitoneal ethanol dose (2.96 g/kg body weight) (Group I), ASA (200 mg/kg body weight) (Group II) and ASA plus ethanol, in the same doses (Group III), or saline (Group IV - control), were administrated. The epithelial alterations were assessed by means of histological and morphometric methods, on posterior dorsal, anterior dorsal and ventral regions of the tongue. ASA reduced, in rat fetuses, the ethanol deleterious effects on nuclear size in the epithelial prickle cell of the lingual mucosa. On the other hand, ASA did not influence the effects of ethanol in both epithelial layers of the lingual mucosa, when the nuclear shape, cell volume or epithelial layers thickness were evaluated.

Effect of acute administration of ethanol on beta-endorphin plasma level in ethanol preferring and non-preferring rats chronically treated with naltrexone

An ample support can be found in professional literature for the hypothesis that the endogenous opioid system plays an important role in developing a craving for alcohol. It is well established that people with a genetic deficit of beta-endorphin are particularly susceptible to alcoholism. In our study, we looked into the beta-endorphin plasma level of animals with high- and low-risk of alcohol dependency after repeated treatment with naltrexone, the opioid antagonist known to be effective in the treatment of alcoholism. We used the Warsaw High Preferring (WHP) and Warsaw Low Preferring (WLP) rats and treated them for 10 days with naltrexone in a dose of 2 mg/kg i.p. One hour before blood collection the rats were injected with a single dose of ethanol. A prolonged naltrexone treatment or a single application of ethanol resulted in the increase of the beta-endorphin plasma level. In the WLP rats repeated naltrexone treatment prevents the ethanol-induced increase in beta-endorphin plasma level. In the WHP rats the level of this peptide was similar to it while they were undergoing the naltrexone treatment or had received a single alcohol injection. This finding supports the proposition that the endogenous opioid system plays an important role in developing a craving for alcohol. It is likely that effectiveness of naltrexone in reducing craving for alcohol results from the attenuation of the rewarding properties of ethanol and restoring the beta-endorphin deficit in reward system.

Rapid ethanol tolerance mediated by adaptations in acute tolerance in inbred mouse strains

It has been postulated that decreased acute sensitivity to ethanol is an important genetically-mediated risk factor for the development of alcoholism. Previous work in mice and rats has indicated that ethanol sensitivity can be reduced in a genotype-dependent manner by a single dose of ethanol 24 h prior to testing, so-called ‘rapid’ tolerance. The current studies were undertaken to determine if the observed rapid tolerance was mediated by alterations in initial sensitivity or acute functional tolerance (AFT), the two primary components of acute sensitivity. Separate groups of C57BL/6, DBA/2, ILS, and ISS inbred mouse strains were administered a single pretreatment dose of saline or ethanol (5 g/kg). The original and modified versions of the loss of righting reflex test, ethanol-induced hypothermia, and ataxia on a stationary dowel rod were tested 24 h later. Dependent on the test and strain, varying degrees of rapid tolerance were observed; a pronounced sensitization was detected in one case. There was a concomitant increase in the rate and/or magnitude of AFT with little change in initial sensitivity suggesting that rapid tolerance was mediated primarily by alterations in AFT. This conclusion may have implications for the contribution of acute sensitivity to human alcoholism.

Effect of a single dose of ethanol on developing peripheral nerve of chick embryos

Fetal Alcohol syndrome (FAS) is a condition occurring in some children of mothers who have consumed alcohol during pregnancy. It is characterized by physical and mental growth retardation, craniofacial anomalies and derangements of numerous body systems. A particular distressing feature of FAS is affection of the nervous system, which manifest as motor and sensory derangements and neurobehavioral deficits. However, no specific changes in the brain and spinal cord that could conclusively explain these neuronal defects have been reported. The aim of this study was to investigate the effects of a single high dose of ethanol exposure during early gestation on the peripheral nerve, with a view to understanding the neuronal disorders appearing in FAS. A chick model of FAS was used and embryos were exposed to 5%, 10% and 15% ethanol immediately after hatching. The effects on general growth and development and on the peripheral nerve of ethanol-exposed embryos were examined following the full period of gestation. There was a significant reduction in crown-rump length, head circumference and body weight in ethanol-exposed chicks as compared with appropriate control groups. The degree of growth retardation among the different alcohol exposed groups was dose dependent and significant prenatal embryo mortality was seen in those exposed to 15% ethanol. In embryos that survived the exposure to 15% ethanol, features of myelin degeneration were observed in the peripheral nerve in the majority of cases. No features of myelin degeneration were observed in embryos exposed to 5% and 10% ethanol or in the control groups. This study demonstrates the direct toxic effects of a single high dose of ethanol on developing embryos in general and the peripheral nerves in particular. Accordingly the pathological changes observed in peripheral nerves could account for some of the neurobehavioral deficits observed in FAS.

A Single Oral Dose of Ethanol Can Alter Transdermal Absorption of Topically Applied Chemicals in Rats

Topical ethanol is used as a dermal penetration enhancer in some commercial products. Previous studies have demonstrated that chronic ethanol consumption can also disrupt skin barrier function, leading to increased transdermal penetration. This observation becomes much more relevant if a single drinking episode induces similar changes. The purpose of this study was thus to examine the transdermal penetration of three model chemicals after acute ethanol consumption. Wistar rats were gavaged with either 10, 6, 4.3, 3, 1.5 g/kg ethanol or saline and allowed to recover for 2 or 24 h. Blood and skin ethanol levels were determined and in vitro penetration experiments performed. The herbicide paraquat, industrial solvent N,N-dimethylformamide (DMF), and insect repellent N,N-diethyl-m-toluamide (DEET) were used as is model chemicals. Absorption was determined and directly compared between ethanol- and saline-treated skin by calculating enhancement ratios. Blood ethanol levels range from 0.25 to 0.015% at 2 h with skin levels at 12-18% of blood values. Ethanol enhances the absorption of paraquat, DMF, and DEET in a dose-dependent fashion. Paraquat and DEET showed no appreciable reduction in enhancement between 2 and 24 h postgavage for the 10-g/kg dose, but DMF did. Enhancement ratios were higher at 24 h for 10 than for 6 g/kg animals, demonstrating a dose-response relationship for recovery time. These studies imply that increased absorption of topical chemical occurs after alcohol ingestion. Both acute and chronic ethanol consumption can compromise the dermal barrier.

Nicotinamide Protects against Ethanol-Induced Apoptotic Neurodegeneration in the Developing Mouse Brain

BackgroundExposure to alcohol during brain development may cause a neurological syndrome called fetal alcohol syndrome (FAS). Ethanol induces apoptotic neuronal death at specific developmental stages, particularly during the brain-growth spurt, which occurs from the beginning of third trimester of gestation and continues for several years after birth in humans, whilst occuring in the first two postnatal weeks in mice. Administration of a single dose of ethanol in 7-d postnatal (P7) mice triggers activation of caspase-3 and widespread apoptotic neuronal death in the forebrain, providing a possible explanation for the microencephaly observed in human FAS. The present study was aimed at determining whether nicotinamide may prevent ethanol-induced neurodegeneration.Methods and FindingsP7 mice were treated with a single dose of ethanol (5g/kg), and nicotinamide was administered from 0 h to 8 h after ethanol exposure. The effects of nicotinamide on ethanol-induced activation of caspase-3 and release of cytochrome-c from the mitochondria were analyzed by Western blot ( n = 4–7/group). Density of Fluoro-Jade B–positive cells and NeuN-positive cells was determined in the cingulated cortex, CA1 region of the hippocampus, and lateral dorsal nucleus of the thalamus ( n = 5–6/group). Open field, plus maze, and fear conditioning tests were used to study the behavior in adult mice ( n = 31–34/group). Nicotinamide reduced the activation of caspase-3 (85.14 ± 4.1%) and the release of cytochrome-c (80.78 ± 4.39%) in postnatal mouse forebrain, too. Nicotinamide prevented also the ethanol-induced increase of apoptosis. We demonstrated that ethanol-exposed mice showed impaired performance in the fear conditioning test and increased activity in the open field and in the plus maze. Administration of nicotinamide prevented all these behavioral abnormalities in ethanol-exposed mice. ConclusionsOur findings indicate that nicotinamide can prevent some of the deleterious effects of ethanol on the developing mouse brain when given shortly after ethanol exposure. These results suggest that nicotinamide, which has been used in humans for the treatment of diabetes and bullous pemphigoid, may hold promise as a preventive therapy of FAS.

A dual effect of N-acetylcysteine on acute ethanol-induced liver damage in mice

Reactive oxygen species (ROS) have been associated with acute ethanol-induced liver damage. N-acetylcysteine (NAC) is a glutathione (GSH) precursor and direct antioxidant. In this study, we investigated the effects of NAC on acute ethanol-induced liver damage. Female ICR mice were administered by gavage with a single dose of ethanol (6g/kg). NAC was administered in two different modes. In mode A, mice were injected with different doses of NAC at 30min before ethanol. In mode B, mice were injected with different doses of NAC at 4h after ethanol. Acute ethanol-induced liver damage was estimated by measuring serum alanine aminotransferase (ALT) activity and histopathological changes. Result showed that a single dose of ethanol (6g/kg) caused a significant increase in serum ALT activity, followed by microvesicular steatosis and necrosis in mouse liver. Pretreatment with NAC significantly protected against acute ethanol-induced liver damage in a dose-independent manner. Correspondingly, pretreatment with NAC significantly attenuated acute ethanol-induced lipid peroxidation and GSH depletion and inhibited hepatic TNF-alpha mRNA expression. By contrast, post-treatment with NAC aggravated ethanol-induced hepatic lipid peroxidation and worsened acute ethanol-induced liver damage in a dose-dependent manner. Taken together, NAC has a dual effect on acute ethanol-induced liver damage. Pretreatment with NAC prevent from acute ethanol-induced liver damage via counteracting ethanol-induced oxidative stress. When administered after ethanol, NAC might behave as a pro-oxidant and aggravate acute ethanol-induced liver damage.

Toxic Alcohol but not Intoxicated-A Case Report

Ethylene glycol is recognised as a potentially lethal poison if ingested. Approximately 100 mls may be fatal in a 70 kg adult. Current Toxbase guidelines are the accepted standard of treatment of such poisonings in the United Kingdom. These guidelines suggest that symptoms of significant poisoning are usually present within 30 minutes of ingestion i.e. ataxia, dysarthria, nystagmus, nausea and vomiting, haematemesis, coma and convulsions. In the absence of these symptoms, metabolic acidosis or ethylene glycol concentration more than 8 mmol/l a single loading dose of ethanol and observation were the recommended course of management until recently. We report a case of a patient who remained relatively asymptomatic for almost 24 hours but then developed clinical symptoms with marked metabolic acidosis and renal impairment requiring intensive treatment including haemodialysis.

Ethyl Sulfate: A Metabolite of Ethanol in Humans and a Potential Biomarker of Acute Alcohol Intake

This study identified ethyl sulfate (EtS) in human urine and compared the excretion characteristics of EtS with that of ethanol and ethyl glucuronide (EtG). Urine samples were collected from healthy subjects after a single ethanol dose, and also selected from routine clinical samples. Simultaneous analysis of EtS and EtG was performed by direct electrospray liquid chromatography-mass spectrometry in the negative ion mode, with selected-ion monitoring of the pseudomolecular ions at m/z 125 for EtS (M(w) 126 g/mol) and m/z 221 for EtG (M(w) 222 g/mol). The identity of EtS in authentic urine specimens was established by co-chromatography with reference substance, the presence of product ions (m/z 97 and 80 from m/z 125) with correct relative intensity, and a correct sulfur isotope ratio for (34)S (m/z 127). After healthy subjects drank ethanol, EtS showed a much longer, dose-dependent elimination half-life than the parent compound. No EtS was detected in urines collected after abstention from ethanol for several days prior to sampling. Among 354 consecutive clinical samples, 86 were positive for both EtS and EtG with a mean EtG/EtS molar ratio of 2.3 (median 1.7). Another three urine samples were only positive for EtS and four only for EtG. The present results confirm that sulfate conjugation is a normal but minor metabolic pathway for ethanol in humans, and EtS a common constituent in the urine after alcohol intake. It is also indicated that the concurrent determination of EtS and EtG will improve sensitivity, when being used as biomarkers of recent drinking.

Acute ethanol exposure impairs angiogenesis and the proliferative phase of wound healing

Acute ethanol exposure represents an increased risk factor for morbidity and mortality associated with surgical or traumatic injury. Despite clinical observations suggesting that ethanol exposure before injury alters tissue repair processes, little direct evidence about the mechanism by which ethanol affects the wound healing process is available. In this study, excisional wounds from female BALB/c mice with or without circulating ethanol levels of 100 mg/dl were used to assess wound closure, angiogenesis, and collagen content. Ethanol exposure resulted in a significant but transient delay in wound closure at day 2 postwounding (28 +/- 4% vs. 17 +/- 1%). In addition, total collagen content was significantly reduced by up to 37% in wounds from ethanol-treated mice compared with controls. The most significant effect of ethanol exposure on wounds was on vascularity because angiogenesis was reduced by up to 61% in wounds from ethanol-treated mice. The reduction in vessel density occurred despite near-normal levels of proangiogenic factors VEGF and FGF-2, suggesting a direct effect of ethanol exposure on endothelial cell function. Further evidence for a direct effect was observed in an in vitro angiogenesis assay because the exposure of endothelial cells to ethanol reduced angiogenic responsiveness to just 8.33% of control in a cord-forming assay. These studies provide novel information regarding the effect of a single dose of ethanol on multiple parameters of the wound healing process in vivo and suggest a potential mechanism by which ethanol impairs healing after traumatic injury.

Multistage Ethanol Sclerotherapy of Soft-Tissue Arteriovenous Malformations: Effect on Pulmonary Arterial Pressure

To retrospectively investigate how repeat injections of absolute ethanol in therapeutic doses, required for multisession sclerotherapy of large high-flow soft-tissue arteriovenous malformations (AVMs) in patients with normal cardiopulmonary function, affect pulmonary arterial pressure (PAP). Study received approval and waiver of informed consent by institutional review board and was conducted in 16 male and 16 female patients with AVMs who underwent repeat sclerotherapy (142 sessions total) with absolute ethanol from July 1997 to December 2003. PAPs were monitored during first session in all patients. In subsequent sessions, PAP was monitored with pulmonary catheter when predicted single dose of ethanol exceeded 3 mL and total amount exceeded 0.25 mL/kg. PAP was measured in 104 sessions. Serum ethanol levels from blood samples obtained at end of each session were reviewed. PAP parameters were analyzed at beginning and end of each session, and highest value was recorded to assess any increase after repeat therapy. Difference between initial and highest PAP values recorded in a session (Delta(max)) was noted to determine any increase during repeat sessions. Possible relationship was reviewed between this value and amount of ethanol used. For sessions without PAP monitoring, mixed model was used for statistical analysis. Total ethanol used was variable. In 43 sessions, highest mean PAP exceeded 25 mm Hg. Incidence of sustained pulmonary hypertension (mean PAP > 25 mm Hg) at end of each session was 30.8% (32 of 104 sessions). Initial PAP parameters did not increase or decrease during repeat sessions. No significant changes in Delta(max) of systolic and mean PAP were observed with increasing number of sessions. Rather, Delta(max) of diastolic PAP was reduced after repeat sessions (P = .03). There was no significant correlation between serum ethanol level and PAP parameters at end of sessions. Relationships between Delta(max) values of systolic, mean, and diastolic PAP and total ethanol used were not significant. High incidence of acute pulmonary hypertension was observed in each sclerotherapy session without lasting effect on PAP.

Alcohol- and Light-induced Electro-oculographic Responses: Variability and Clinical Utility

The alcohol-induced electro-oculographic (EOG) response has been proposed by Arden as an indicator of retinal pigment epithelial (RPE) integrity. We have evaluated the consistency of the alcohol-EOG with respect to clinical applicability and compared this response to the ISCEV-standard EOG. We recorded, in a group of normal subjects (n=29, 14 men with mean age 42+/-11 years and 15 women with mean age 36+/-13 years), the alcohol response to a single oral dose of ethanol at 160 mg/kg (as 40 proof vodka, drunk in 15 s after 12 h of fasting), followed by an ISCEV-standard EOG 90 min after alcohol administration. Blood alcohol levels were monitored at regular intervals with a breath analyzer. We found a wide range of amplitudes in both light and alcohol responses among participants, from minimal to large values. Subjects had a wide range of blood alcohol concentrations from 0.02 to 0.10%; near the time of the response peak, but there was no relationship between alcohol levels and peak/baseline ratios. In addition, there was no relationship between alcohol peak/baseline ratio and the Arden ratio. Neither the alcohol nor the light response parameters showed any relationship with age or gender. Some of the inter-individual variability in the EOG response to alcohol may reflect variable absorption of oral alcohol. The alcohol-induced EOG has too broad a range of responses to be useful clinically for the one-time evaluation of individual patients. We have similar concerns regarding clinical applications of the standard light-induced EOG.

Orally administered ethanol: transepidermal pathways and effects on the human skin barrier

Ethanol intake is associated with a variety of skin diseases. The aim of the present study was (1) to identify the pathways of release of orally administered ethanol through the skin, and (2) to investigate the effects of a single oral dose of ethanol on the penetration of topically applied substances into the skin. Ethanol evaporation via the skin was measured using the new technique of ion mobility spectrometry (IMS). Transepidermal water loss (TEWL) and skin surface temperature were simultaneously measured before and after ethanol consumption. Measurements were performed on skin sites with different stratum corneum (SC) thickness, and density of follicles and sweat glands. These appendages were selectively sealed to investigate their participation in ethanol evaporation. The penetration of a topically applied UV filter substance was studied before and after ethanol consumption after removing the SC with adhesive tape. Ethanol evaporation was measured within 5 min of consumption, while the skin surface temperature remained nearly constant. The sealing of the appendages did not have a significant effect on ethanol evaporation. On the forehead, a higher TEWL value was measured than on the forearm. On both skin sites, an increase in TEWL was observed after ethanol ingestion. No influence of orally administered ethanol on the penetration of the topically applied UV filter substance was observed. The results indicate that ethanol evaporation occurs via the lipid layers without a significant effect on the penetration of the topically applied substance.

In the adult CNS, ethanol prevents rather than produces NMDA antagonist-induced neurotoxicity

Single doses of an NMDA antagonist cause an adult or a prepubertal form of neurodegeneration, depending on the age of the animal. Single doses of ethanol (EtOH) by blocking NMDA receptors produce apoptotic neurodegeneration in young animals. This capability could account, in part, for the ability of EtOH to produce the fetal alcohol syndrome. We investigated whether EtOH could produce NMDA antagonist-induced neurotoxicity (NAN), a different neurotoxicity that is seen only in adult animals. In spite of producing blood EtOH levels (30 to 600 mg/dl) known to block NMDA receptors, EtOH was unable to produce neurotoxicity in the adult central nervous system (CNS). Moreover, EtOH in a dose-dependent fashion (ED 50=138 mg/dl) prevented the selective and powerful NMDA antagonist, MK-801, from producing NAN in adult animals, suggesting that activity at another site might be negating the neurotoxic effect of EtOH's inherent NMDA antagonistic activity. Because GABA A agonism and non-NMDA glutamate antagonism, properties which EtOH possesses, can prevent NAN, we proceeded to study whether GABA A antagonists (or agents capable of reversing EtOH's GABAergic effects) and non-NMDA agonists could reverse EtOH's protective effect. Bicuculline, Ro15-4513, finasteride, kainic acid or AMPA, alone or in combination, did not significantly reverse EtOH's protective effect. Given that EtOH has effects on a wide range of ion channels and receptors, determining the precise mechanism of EtOH's protective effect will take additional effort. The inability of EtOH to acutely produce NAN in the adult CNS indicates that, in contrast to fetuses, brief exposure of the adult CNS to EtOH is non-toxic for neurons.

Effect of a single dose of ethanol on developing skeletal muscle of chick embryos

Fetal alcohol syndrome is a condition occurring in some children of mothers who have consumed alcohol during pregnancy. Many of these affected children show retarded physical growth in the postnatal period despite adequate nutrition. On the basis of findings from studies with animals, it has been proposed that this is due to allometric retardation of growth of skeletal muscle, although the exact reasons for this are not known. The aim of the current study was to examine the structural changes in skeletal muscle in fetal alcohol syndrome in an attempt to understand the mechanisms of growth retardation in fetal alcohol syndrome. Chick embryos were exposed to single doses of 5%, 10%, and 15% ethanol, and the effects on the general growth and development, as well as on the skeletal muscle, of these chicks were studied. There was a significant retardation in crown rump length, head circumference, and body weight in ethanol-exposed chicks when these parameters were compared with findings for appropriate control groups. This retardation was associated with significant and proportionate reductions in the weights of skeletal muscles. Microscopic examination of skeletal muscle showed areas of neutrophil infiltration and necrosis, suggestive of muscle damage, in chicks exposed to 10% and 15% ethanol. Thus, findings of the current study demonstrate the direct toxic effects of a single dose of ethanol on developing embryos in general and skeletal muscle in particular. The pathologic changes seen in skeletal muscle could account for the failure in postnatal growth in fetal alcohol syndrome.