C. J. Peter Eriksson

The determination of acetaldehyde in blological samples by head-space gas chromatography

Abstract A method for the determination of acetaldehyde (AcH) in biological samples by head-space gas chromatography is presented. Human venous blood (antecubital), rat blood (heart-punctured) rat liver (freeze-clamped), and rat and mouse brain (freeze-clamped) were used as the biological samples. The method involves two steps, in the first of which the samples are deproteinized with perchloric acid (PCA). Rat blood can, alternatively, be hemolyzed with water. In the second step, the deproteinized supernatant or hemolyzed blood is pipetted into a serum bottle, which is sealed with a rubber stopper and brought to 65°C in a sampling turntable. Head-space samples are then automatically taken for GLC analysis. Ethanol causes a nonenzymatic formation of AcH in the PCA supernatants of liver and brain, which can be inhibited by the use of thiourea. This reaction is minor in the blood supernatants and cannot be inhibited there by thiourea. The method described measures the total AcH content without regard to any binding. Some of the AcH in rat blood was shown to be bound.

The distribution and metabolism of acetaldehyde in rats during ethanol oxidation-I. The distribution of acetaldehyde in liver, brain, blood and breath.

Abstract An in vivo investigation was made of the distribution of acetaldehyde (AcH) during ethanol metabolism. Different doses of ethanol were administered orally to male and female Sprague-Dawley rats ( n = 96) and AcH measured at various times thereafter in the liver, blood, brain and breath. The results showed that the liver was the primary site for the oxidation of the ethanol-derived AeH. Only a small amount of the total AcH formed in this organ escaped into the rest of the body, but this amount increased with increased hepatic ethanol concentration. The hepatic AcH level was higher in male rats than in females with the same hepatic ethanol concentration. The extrahepatic AcH levels in arterial cerebral and in peripheral tail blood correlated well with the corresponding hepatic AcH levels. The bulk of the hepatic AcH output was eliminated extrahepatically, thus drastically changing the AcH level from that initially leaving the liver. Sex differences also appeared in the extrahepatic blood AcH levels, with the female rats displaying higher AcH levels, as a result of their less efficient extrahepatic AcH elimination. The peripheral tail blood AcH was found to be similar to the AcH level of the venous blood before the hepatic blood AcH is added to it. Regardless of the AcH levels in the liver and blood, no AcH was found in the brain. Less than 5 per cent of the hepatic AcH output was exhaled. Pentobarbital anaesthesia strongly depressed the amount of AcH exhaled. The AcH in the breath did not reflect the hepatic AcH as well as the blood AcH levels did.

Involvement of corticosterone in the modulation of ethanol consumption in the rat

Several studies report that rats exposed to stressful conditions may increase their ethanol consumption. Stress is accompanied by a rise in the secretion of adrenocortical hormones, and the possibility that these hormones exert an influence on ethanol consumption should be considered. The present investigation addressed this issue by studying the effect of adrenalectomy (ADX) and subsequent corticosterone (CORT) or aldosterone (ALDO) treatment on ethanol intake. The results showed that ADX rats decreased their ethanol intake compared to the sham-operated controls and that treatment with CORT restored the intake of ethanol to the preoperative level. In contrast, treatment with ALDO (0.25 or 0.75 mg/kg) had no effect on ethanol intake. Biochemical analyses showed increases in monoamine turnover in the brain stem and limbic forebrain after ADX. The reduction of ethanol consumption caused by ADX may thus be specifically attributed to the loss of one of the adrenal hormones, CORT. The results indicate that CORT may be a factor of importance in the modulation of alcohol consumption.

Effect of moderate alcohol consumption on plasma dehydroepiandrosterone sulfate, testosterone, and estradiol levels in middle-aged men and postmenopausal women: a diet-controlled intervention study

BACKGROUND Moderate alcohol consumption is inversely associated with cardiovascular diseases. Changes in hormone levels might in part help explain the positive health effect. This study was performed to examine the effect of moderate alcohol consumption on plasma dehydroepiandrosterone sulfate (DHEAS), testosterone, and estradiol levels. METHODS In a randomized, diet-controlled, crossover study, 10 middle-aged men and 9 postmenopausal women, all apparently healthy, nonsmoking, and moderate alcohol drinkers, consumed beer or no-alcohol beer with dinner during two successive periods of 3 weeks. During the beer period, alcohol intake equaled 40 and 30 g per day for men and women, respectively. The total diet was supplied and had essentially the same composition during these 6 weeks. Before each treatment there was a 1 week washout period, in which the subjects were not allowed to drink alcoholic beverages. At the end of each of the two experimental periods, fasting blood samples were collected in the morning. RESULTS Moderate alcohol consumption increased plasma DHEAS level by 16.5% (95% confidence interval, 8.0-24.9), with similar changes for men and women. Plasma testosterone level decreased in men by 6.8% (95% confidence interval, -1.0- -12.5), but no effect was found in women. Plasma estradiol level was not affected. Serum high-density lipoprotein cholesterol level increased by 11.7% (95% confidence interval, 7.3-16.0), with similar changes for men and women. The overall alcohol-induced relative changes in DHEAS, testosterone, and estradiol correlated positively with the relative increase in high-density lipoprotein cholesterol (adjusted for the relative change in body weight); however, findings were only borderline significant for DHEAS and estradiol (r = 0.44, p = 0.08; r = 0.32, p = 0.21; and r = 0.46, p = 0.06, respectively). CONCLUSIONS A protective effect of moderate alcohol consumption for cardiovascular disease risk may in part be explained by increased plasma DHEAS level.

Human blood acetaldehyde concentration during ethanol oxidation (update 1982).

A wide variety of levels of human blood acetaldehyde have been reported in the past. During the last few years, however, it has become increasingly evident that most, if not all, of the previously observed acetaldehyde concentrations during normal (i.e., no deficiency in, or inhibition of, aldehyde dehydrogenase activity) ethanol oxidation merely reflected artefactual acetaldehyde formed during the analytical procedures. The artefactual acetaldehyde formation, which occurs mainly during blood protein precipitation, is effectively minimized by the recently improved PCA method in which blood is immediately mixed with a perchloric acid-saline solution, and by the semicarbazide method in which blood is treated with a fresh isotonic semicarbazide solution before removal of the plasma. Nevertheless, a procedure involving control blood with ethanol added should be employed to control for any artefactual acetaldehyde still produced. Based on the improved analytical procedures, no detectable acetaldehyde was found in the venous blood of Caucasian subjects after acute ethanol intake.

The determination of acetaldehyde in human blood by the perchloric acid precipitation method: The characterization and elimination of artefactual acetaldehyde formation

Abstract An improved method for treating human blood samples taken for acetaldehyde analysis is presented. The protein precipitation is performed by instant and thorough mixing of the blood sample in a saline solution of perchloric acid. This procedure effectively reduces the artefactual formation of acetaldehyde that occurs during the protein precipitation. The remaining artefactual acetaldehyde, which is mainly formed during the incubation prior to head-space analysis, can be corrected for by a correction curve made using control blood to which ethanol has been added.

Sex hormones and adrenocortical steroids in men acutely intoxicated with ethanol

The plasma or serum concentrations of testosterone, LH, FSH, PRL, cortisol, 17-hydroxyprogesterone, androstenedione, dehydroepiandrosterone, estrone and estradiol were monitored in 8 healthy male volunteers for a period of 48 hr after administration of one large dose of ethanol (1.75 g/kg BW) within the first 3 hr of the experiment. Each subject served as his own control in an identical experiment without ethanol. Blood alcohol concentration reached a maximum of 1.51 +/- 0.08 g/l (mean +/- SEM) 4 hr after the start of drinking. The maximum decrease in serum testosterone was observed at 12 hr when the serum concentrations of gonadotropins were still unchanged. The decrease in serum testosterone persisted at 24 hr despite increases in the serum levels of LH and FSH. The serum or plasma concentrations of PRL, cortisol, 17-hydroxyprogesterone, androstenedione and dehydroepiandrosterone were clearly increased 4 hr after the start of drinking. The increase in serum cortisol lasted as long as the decrease in serum testosterone. No significant changes were found in plasma concentrations of estrone and estradiol. Our results suggest that in addition to direct testicular effects of alcohol, increased adrenal secretion of cortisol may contribute to the decrease in serum testosterone in men acutely intoxicated with ethanol.

Motor impairment, narcosis and hypothermia by ethanol: Separate genetic mechanisms

The AT and ANT rat lines, developed by selective outbreeding for differential ethanol-induced motor impairment, were tested for their sensitivity to the hypothermic and narcotic (loss of righting reflex) effects of ethanol. In contrast to the large differences between the lines in their degree of motor impairment, as measured with both the tilting-plane and rotarod tests, only minor differences were observed in duration of loss of righting reflex or hypothermia. Therefore, we suggest that genetically determined factors influencing motor impairment are for the most part dissociated from the factors determining the hypothermic and narcotic effects of ethanol.

Evaluation of Aldehyde Dehydrogenase 1 Promoter Polymorphisms Identified in Human Populations

BACKGROUND Cytosolic aldehyde dehydrogenase, or ALDH1A1, functions in ethanol detoxification, metabolism of neurotransmitters, and synthesis of retinoic acid. Because the promoter region of a gene can influence gene expression, the ALDH1A1 promoter regions were studied to identify polymorphism, to assess their functional significance, and to determine whether they were associated with a risk for developing alcoholism. METHODS Sequence analysis was performed in the promoter region by using Asian, Caucasian, and African American subjects. The resulting polymorphisms were assessed for frequency in Asian, Caucasian, Jewish, and African American populations and tested for associations with alcohol dependence in Asian and African American populations of alcoholics and controls. The functional significance of each polymorphism was determined through in vitro expression analysis by using HeLa and HepG2 cells. RESULTS Two polymorphisms, a 17 base pair (bp) deletion (-416/-432) and a 3 bp insertion (-524), were discovered in the ALDH1A1 promoter region: ALDH1A1*2 and ALDH1A1*3, respectively. ALDH1A1*2 was observed at frequencies of 0.035, 0.023, 0.023, and 0.012 in the Asian, Caucasian, Jewish, and African American populations, respectively. ALDH1A1*3 was observed only in the African American population, at a frequency of 0.029. By using HeLa and HepG2 cells for in vitro expression, the activity of the luciferase reporter gene was significantly decreased after transient transfection of ALDH1A1*3-luciferase compared with the wild-type construct ALDH1A1*1-luciferase. In an African American population, a trend for higher frequencies of the ALDH1A1*2 and ALDH1A1*3 alleles was observed in a population of alcoholics (p = 0.03 and f = 0.12, respectively) compared with the control population. CONCLUSIONS ALDH1A1*2 and ALDH1A1*3 may influence ALDH1A1 gene expression. Both ALDH1A1*2 and ALDH1A1*3 produce a trend in an African American population that may be indicative of an association with alcoholism; however, more samples are required to validate this observation. The underlying mechanisms contributing to these trends are still unknown.

Mean cell volume and gamma-glutamyl transferase are superior to carbohydrate-deficient transferrin and hemoglobin-acetaldehyde adducts in the follow-up of pregnant women with alcohol abuse

Background and Objective. To compare the usefulness of carbohydrate‐deficient transferrin (CDT), the ratio of CDT to total transferrin, and hemoglobin‐acetaldehyde adducts with mean cell volume (MCV) and gamma‐glutamyl transferase (GGT) in the follow‐up of alcohol abuse during pregnancy.