Effects of ethanol and acetaldehyde on cultured pre-implantation mouse embryos

Summary Pre-implantation 2-cell stage mouse embryos, obtained from superovulated CF-1 mice, were exposed to ethanol and acetaldehyde through the culture medium for 60 min followed by a 105-h incubation period. Control and ethanol exposed embryos survived equally well in ethanol concentrations as high as 800mg/100 ml medium and acetaldehyde levels up to 10 mg/100 ml medium.     

Ethanol metabolism inDrosophila melanogaster

Summary A quantitative study of the transformation of ethanol into acetaldehyde shows that, inDrosophila melanogaster, the mitochondrial ethanol oxidizing system is not very active but that the part played by catalase appears more important than expected. For a strain without alcoholdehydrogenase, ethanol is highly toxic. The presence of acetaldehyde in the culture medium is toxic for all the strains studied. But, since even a strain without any aldehydeoxidase lives normally, the metabolic production of acetaldehyde does not seem dangerous.     

Ethanol metabolism in Drosophila melanogaster.

A quantitative study of the transformation of ethanol into acetaldehyde shows that, in Drosophila melanogaster, the mitochondrial ethanol oxidizing system is not very active but that the part played by catalase appears more important than expected. For a strain without alcoholdehydrogenase, ethanol is highly toxic. The presence of acetaldehyde in the culture medium is toxic for all the strains studied. But, since even a strain without any aldehydeoxidase lives normally, the metabolic production of acetaldehyde does not seem dangerous.     

Acetaldehyde metabolism inDrosophila melanogaster

Summary A quantitative study on in vitro acetaldehyde degradation in homogenates fromDrosophila melanogaster files shows that aldehyde oxidase plays the major part in acetaldehyde detoxification. However, in a strain, celed AO null, because itsAldox locus produces no aldehyde-oxidase, acetaldehyde is also degradated by a still unknown mechanism. Alcoholdehydrogenase which is responsible for the dehydrogenation of ethanol in acetaldehyde, appears to catalyze the reversed reactions as wel, regenerating ethanol fromacetaldehyde.This work was supported in part by a grant from the FNRS of Belgium.     

Effects of streptozotocin on early rat embryos grown in culture

Summary Addition of 1 mg/ml streptozotocin to serum in which 10-day rat embryos are cultured reduces their growth and viability. There is therefore a risk that administration of this drug to pregnant animals to induce diabetes could also have direct, deleterious effects on the embryos.     

Effects of streptozotocin on early rat embryos grown in culture.

Addition of 1 mg/ml streptozotocin to serum in which 10-day rat embryos are cultured reduces their growth and viability. There is therefore a risk that administration of this drug to pregnant animals to induce diabetes could also have direct, deleterious effects on the embryos.     

Effect of different methods of exposure to cyproterone acetate on mortality in chick embryos

Summary 33-h chick embryos exposed to 0.25 mg or 0.50 mg cyproterone acetate injected into the yolk sac showed a significantly lower mortality rate than embryos receiving the same dosage applied directly onto the developing blastodisc.This work was supported by a Government Research Support Grant awarded to Louisiana State University School of Medicine. Cyproterone acetate supplied through courtesy of Schering AG, Berlin, West Germany.     

The effects of naloxone on the analgesic activities of general anaesthetics

Summary Inhaled concentrations of nitrous oxide (80%), halothane (0.5%), trichloroethylene (0.5%) and s.c. ethanol (1 ml/kg) caused similar degrees of excitation and ataxia in mice. Nitrous oxide, tricholoroethylene and ethanol caused analgesia (hot plate and writhing tests), but only that caused by nitrous oxide was antagonized by naloxone (20 mg/kg). Halothane lacked analgesic activity.     

Lowering of liver acetaldehyde but not ethanol concentrations by pretreatment with taurine in ethanol-loaded rats

A rise in blood and liver acetaldehyde concentrations following ethanol loading (1.5 g/kg b.wt) was significantly reduced when rats were pretreated orally with taurine (0.5 g/kg), a potent in vitro activator of yeast aldehyde dehydrogenase. This taurine pretreatment produced a 4-fold increase in liver taurine content.     

Serum cholesterol levels in a Nigerian population sample

Serum cholesterol was determined in 104 healthy Nigerians (57 males and 47 females). The average cholesterol concentration was 187 +/- 72.8 mg/100 ml (mean +/- SD) with a range of 60-480 mg/100 ml. Cholesterol levels were higher in males than in females and increased with age. Distribution of cholesterol level was generally skew to the left.     

Regulation of enzymes of ethanol metabolism in yeast (Rhodotorula gracilis).

The three enzymes of ethanol metabolism alcohol dehydrogenase, aldehyde dehydrogenase and acetyl-CoA synthetase in the obligate aerobic yeast Rhodotorula gracilis are repressed by glucose and induced by C2 metabolic fuels with a regulatory pattern indicating a correlation in the control mechanisms. To try an identification of the molecular signals involved in the transmission of the inducing stimulus, experiments were carried out by blocking with 2 mM pyrazole the ethanol acetaldehyde metabolic step. Results indicate that ethanol is not specifically required as a molecular signal for induction.     

The effect of 5-bromodeoxyuridine on mouse embryos during neurulation in vitro

Mouse embryos explanted at various stages during neurulation were cultured for 20-28 h in the presence of 25-900 micrograms/ml of 5-bromodeoxyuridine (BUdR). BUdR strongly inhibited closure of the cranial neural tube, which was found to be stage-dependent. When mouse embryos were exposed to BUdR after development of the concave curvature in the neuroepithelium of the midbrain to the upper hindbrain regions, they became insensitive to the drug-induced open cranial neural tube. Histological observations showed that BUdR interfered with interkinetic migration and cytokinesis of the neuroepithelial cells. These cellular abnormalities were not dependent on the morphological development of the cranial neural folds. The 3H-BUdR experiment confirmed that the label was mostly incorporated into the DNA fraction.     

Lowering of liver acetaldehyde but not ethanol concentrations by pretreatment with taurine in ehtanol-loaded rats

Summary A rise in blood and liver acetaldehyde concentrations following ethanol loading (1.5 g/kg b.wt) was significantly reduced when rats were pretreated orally with taurine (0.5 g/kg), a potent in vitro activator of yeast aldehyde dehydrogenase. This taurine pretreatment produced a 4-fold increase in liver taurine content.     

Sur l'interaction entre aldéhydes ou réductones et acides aminés ou protéines

Summary Proteins were exposed to acetaldehyde vapour or mixed with glucose in solution and the basic groups determined by their dy binding capacity. Only serum albumin shows a marked decrease of basic groups and of the carbon/nitrogen ratio as a sign of condensation of aldehyde and amine groups. These results were corroborated by the direct estimation of the aldehyde resine formed on the protein: serum albumin and fibrin treated with acetaldehyde vapour contained 5 to 10 times more resin than the other proteins examined. No rapid combination between serum proteins and glucose could be demonstrated by the dy method or by the kinetics of change of pH. The slow reaction seems not to be dependent on denaturation.     

Effect of sex hormones on uric acid metabolism in rats.

The effects of sex hormones on purine metabolism were investigated in rats. No influence on purine synthesis was shown by the injection of estrogen and androgen. The plasma urate levels were significantly lowered from 2.43 +/- 1.04 mg/100 ml to 1.53 +/- 0.57 mg/100 ml by the injection of progesterone. Urinary excretion of uric acid plus allantoin was slightly reduced. These results suggested that progesterone may influence age and sex differences in human plasma urate levels.     

Suppression by ascorbic acid of neuromuscular fatigue due to sound-alcohol synergy]

The interaction between effects of ethanol ingestion and those of infrasound on neuro-muscular fatigue in the animal is abolished by ascorbic acid. The relevant mechanism is in acetaldehyde detoxification.     

Regulation of enzymes of ethanol metabolism in yeast (Rhodotorula gracilis)

Summary The three enzymes of ethanol metabolism alcohol dehydrogenase, aldehyde dehydrogenase and acetyl-CoA synthetase in the obligate aerobic yeastRhodotorula gracilis are repressed by glucose and induced by C₂ metabolic fuels with a regulatory pattern indicating a correlation in the control mechanisms. To try an identification of the molecular signals involved in the transmission of the inducing stimulus, experiments were carried out by blocking with 2 mM pyrazole the ethanol acetaldehyde metabolic step. Results indicate that ethanol is not specifically required as a molecular signal for induction.This work was supported by a grant from the Italian Consiglio Nazionale delle Ricerche.     

Effects of acetaldehyde and/or ethanol on neutral amino acid transport systems in microvillous brush border membrane vesicles prepared from human placenta

Summary At 20 mM of acetaldehyde, the activities of three transport systems of L-alanine distinguished by the difference in their cation dependence, namely 1) Na⁺-specific, 2) Li⁺-dependent, and 3) Na⁺-independent systems, were significantly reduced in a similar manner. Only the Li⁺-dependent system was selectively inhibited at toxic concentrations of acetaldehyde and ethanol.     

Periimplantation-like growth and development of mouse blastocysts in medium containing horse serum

Horse serum (HS) supported growth and differentiation of blastocysts as well as or better than fetal bovine serum (FBS) (p less than 0.01) as measured by a) the onset of trophoblastic outgrowth, b) the size of the resultant outgrowths, c) the size of nuclei in trophoblasts after their outgrowth and d) the size of the inner cell mass in outgrowths. Moreover, polyamines were found to be approximately 10-100 times less toxic to embryos when added to medium containing HS than when the medium contained FBS.     

Persistence of added retinoids in organ culture media during induction of mucous metaplasia and glandular morphogenesis in hamster cheek pouches

The retinoid concentration (determined colorimetrically) did not change significantly in retinyl acetate-supplemented (6 micrograms/ml) Eagle's Minimal Essential Medium containing 10% fetal calf serum when stored at -20 or 4 degrees C over 7 days. After the medium was incubated at 37 degrees C for 48 h, 37-49% of the retinoid remained, whether or not tissue (neonatal Syrian hamster cheek pouch) was present, and irrespective of explant age. The normal retinoid level in the tissue was approximately 0.25 micrograms per gram. Therefore, neonatal hamster cheek pouches, incubated in medium with the addition of 6 micrograms of retinyl acetate per ml of medium and undergoing mucous metaplasia and some mucous gland morphogenesis, were continually being exposed to retinoid levels which, though gradually decreasing, remained well above their normal physiological level.