Gender differences in ethanol oxidation and injury in the rat stomach

Gender differences in gastric cancer incidence in elderly former drinkers

Although numerous studies have been done on gastric cancer and alcohol consumption, results from these studies are inconsistent. We conducted a population-based, prospective cohort study to establish a relationship between alcohol and gastric cancer according to gender. The cohort consisted of elderly (>64 years of age) subjects at the baseline of 1993-1998. Baseline information was surveyed using a self-administered questionnaire. Gastric cancers were identified by the National Cancer Registry. Cox proportional hazards models were used to calculate relative risks with 95% confidence intervals. A follow up of 116,997.1 person-years of the 13,396 subjects revealed 151 newly diagnosed gastric cancers (80 men and 71 women). The risk of gastric cancer was higher by a factor of three among female former drinkers (adjusted relative risk 2.85 [95% confidence interval 1.11-7.32]) compared to current and nondrinkers. Female former drinkers showed greater alcohol consumption than current drinkers (36.5g/week vs. 16.4g/week; P<.0001) and a longer duration of alcohol consumption than did current drinkers (24.5 years vs. 18.46 years; P<.0001). Female subjects with more than 110g of weekly alcohol consumption had an increased risk of developing gastric cancer (adjusted relative risk 2.23 [95% confidence interval 0.79-6.29]), although the result was statistically insignificant. No relationship was observed for male subjects. The relationship between alcohol and gastric cancer differs according to gender. Alcohol consumption may increase the risk of gastric cancer in women, and the risk elevation may persist for several years after drinking ceases.

Ebselen as protection against ethanol-induced toxicity in rat stomach

The mucosal protective effect of ebselen was examined in an ethanol-induced rat gastric lesion model. Examination of gastric tissue samples by light microscopy showed that i.g. exposure to 50% ethanol induced gastric injury, which was more prominent in female rats. Ethanol did not effect the gastric acid secretion examined by means of H(+)-K+ATPase, the increment of which might be harmful in the stomach. But ebselen with or without ethanol kept H(+)-K+ATPase below control levels. Gastric alcohol dehydrogenase (ADH) was mainly responsible for oxidation of ethanol in the stomach before it enters the bloodstream. I.g. ethanol exposure inhibited the ADH activity but ebselen eliminated the ethanol-induced inhibition of this enzyme. Therefore, ebselen exhibited a beneficial effect by increasing the gastric ethanol metabolism and by ameliorating the possible tissue toxicity of ethanol. Consistently, we also found that ebselen diminished the blood ethanol level. A gender difference in the blood ethanol levels existed following the same dose of ethanol but there was no difference in ADH activity. Histologically, mucosal injury following ebselen exposure together with ethanol was less severe compared with ethanol treatment alone. We concluded that the decrease in ethanol-induced mucosal injury following ebselen may have contributed to the inhibition of H(+)-K+ATPase and the activation of ADH by ebselen.

The Effects of Salty and Nonsalty Food on Peak Breath Alcohol Concentration and Divided Attention Task Performance in Women

There is recent evidence that gender-based patterns of alcohol consumption are becoming less dissimilar and that, per capita, women are consuming more alcohol than ever before. Therefore, a better understanding of the acute effects of moderate alcohol consumption in women is essential to establishing reliable health and safety educational information. To address one component of health and safety information, we sought to determine if peak breath alcohol concentrations (BAC) could be manipulated by varying the amount of sodium our women participants ingested in a test meal. We also measured the association between BAC and the participant's performance on a divided attention (DA) task. The 12 participants were trained to use a computer-generated DA task and subsequently participated in all of four experimental conditions. During each experimental session the participant consumed a placebo drink or a drink containing 0.6 g/kg ethanol and a 220-kcal portion of salted or unsalted pretzels. She then performed four 15-min trials of the DA task, after which the BAC was measured and recorded. Reaction times and mean tracking error were recorded for each DA trial. Experimental sessions took place at the same time on days 7, 8, 9, and 10 of the participant's menstrual cycle. The BAC was significantly higher in the ethanol plus sodium condition than in the ethanol with no sodium condition. Reaction times and tracking tasks were impaired in all ethanol conditions. Scores on the DA tasks obtained from the high-sodium group did not differ significantly from those of the low-sodium group. When health care personnel provide drug education for women clients, the possible BAC-elevating effects of consuming high-sodium foods while drinking alcoholic beverages should be discussed.

Gender differences in the brain: implications for the study of human alcoholism

Gender differences in alcohol intake and response to alcohol may be influenced by basic variations in the organization and modulation of male and female brains. Although a number of genetic, social, environmental, and metabolic factors have been proposed to explain the gender differences observed in risk for alcoholism, alcohol intake, and medical consequences of excessive alcohol intake, very little attention has been given to the role of gender differences in the brain regarding alcohol use. Recent evidence documents the influence of neurosteroids on neurotransmitter activity in the brain and the impact of alcohol on neurosteroid levels. Neurosteroids are found in different levels in males and females during development and throughout life, depending on factors such as age, stage of development, estrous and menstrual cycles, and stress. This study discusses the hypothesis that many of the gender differences observed concerning alcohol use and misuse are determined by gender differences in the brain, which in turn differentially influence the behavioral and neurochemical responses of males and females to alcohol.

Sex differences in schedule-induced alcohol consumption

Six female and five male Wistar rats obtained food by pressing a lever on a fixed-interval (FI) 60-s schedule in the presence of a sipper tube which allowed access to an alcohol solution. Systematic manipulation of the alcohol concentration revealed that male rats consumed higher alcohol concentrations (v/v) than female rats to obtain maximum alcohol intake (g ETOH/kg) during an experimental session. Males also reached higher blood alcohol levels (BALs) than females. Individual lick rates varied over a small range when the FI schedule parameter was manipulated (20 s and 180 s) during probe sessions. Very few licks were observed when all pellets were presented at the beginning of the session, during extinction, or during sessions in which only a few pellets were presented. Reduction of the solution's alcohol concentration to half the maximum concentration or presentation of distilled water resulted in increased lick rates at most values of the FI schedule in four of the five male subjects, but not in female subjects. Alcohol intake during sessions in which half the maximum alcohol concentration was available was lower than that observed during sessions in which subjects consumed the maximum alcohol concentration. The lick rate data in conjunction with those on alcohol intake suggest that male rats, but not female rats, maintained blood alcohol concentrations at levels which they had also reached during sessions in which the maximum alcohol concentration was available from the sipper tube.