The effect of ethanol upon early development in mice and rats. I. In vivo effect upon preimplantation and early postimplantation stages

The preimplantation and early postimplantation effect of chronic alcohol consumption (at least a month before mating and during pregnancy until killing) and of acute ethanol intoxication during the preimplantation period (i.v. infection of ethanol) was studied on albino rats (Wistar) and albino mice (RAP). The main results were as follows: Chronic alcoholization. Rats: significant retardation of preimplantation development and in early postimplantation stages; a tendency of lowering of the mean litter size. Mice: significant increase of the number of preimplantation pathological forms; a tendency of lowering of the mean litter size. Pathological changes show, both in rats and mice, an obvious "litter effect". Acute ethanol intoxication. Rats: significant retardation in some litters, normal or even advanced development in others. This effect differs from the previously reported effect of acute ethanol intoxication during early postimplantation stages. The results obtained attest the prenatal noxious effect of chronic ethanol consumption in both species used and of acute ethanol intoxication during preimplantation development upon early postimplantation development in rats. Within the limits of extrapolation possibilities, they represent a risk signal for other species (including human).     

The effect of ethanol upon early development in mice and rats. III. In vivo effect of acute ethanol intoxication upon implantation and early postimplantation stages in mice

Female albino mice (RAP strain) were injected intravenously with absolute alcohol diluted aa by a.d., on days 2, 3 and 4 of pregnancy respectively. Macroscopically pregnant and empty uteri were controlled by microscopic examination. The developmental rate of postimplantation embryos was controlled by a previously reported biometrical method. The acute ethanol intoxication did not influence the postimplantation developmental rate (except for the appearance and development of the allantoic bud). In some of the uteri of the treated females (mainly of those treated on day 4), free blastocysts were found in the uterine lumen on day 9 of pregnancy, supposedly due to the deleterious effect of ethanol intoxication on central and local factors of implantation. Regressive changes of the decidua and consecutive embryonic death found in two litters may be caused by the same deleterious effect or (and) by inflammatory changes present in the endometrium of some control and treated females. The acute ethanol intoxication lowered the mean litter size in all the experimental groups.     

The effect of ethanol upon early development in mice and rats. V. In vivo effect of acute preimplantation intoxication with or without previous chronic alcoholization

Albino rats (Wistar) and albino mice (RAP) were either injected intravenously with ethanol during the preimplantation period (day 4 and 3, respectively) or injected in the same way after a previous chronic alcoholization (peroral consumption of 20% ethanol for 50-60 and 32-35 days, respectively before mating, adding the days until killing). The control of possible effects was performed on day 5 (rats) and 4 (mice) by usual flushing, examination and photographing of oviductal and uterine embryos. A group of albino rats, with chronic alcoholization, was controlled for late, fetal effects (resorption rate, skeletal control, possible ocular anomalies). The main results obtained were as follows: Acute ethanol intoxication. Rats: significant increase of pathological, fragmented preimplantation embryos with a marked "litter effect". Mice: no deleterious effect upon preimplantation development. Chronic alcoholization + acute ethanol intoxication. Rats: significant retardation of the preimplantation development rate and a significant increase of the number of pathological, fragmented embryos with a marked "litter effect". Mice: demonstrable advance of preimplantation development and migration rate. Chronic alcoholization--late fetal control in rats: the increase of resorption rate; the more frequent absence of sacral vertebrae; very rare rib anomalies and the absence of ocular malformations.     

The effect of ethanol upon early development in mice and rats. VIII. The effect of chronic consumption of some beverages upon preimplantation development in rats

The effects of chronic consumption of some beverages (plum-brandy 24% and cognac 20%) upon preimplantation development in rats were studied. The control of possible effects was performed on day 5 by usual flushing, examination and photographying of oviductal and uterine embryos. In order to evaluate the effect of the beverage applied, the following criteria were used: mean litter size, migration of the embryos from the oviduct to the uterus, the developmental stage attained by the pre-implantation embryos and the appearance of pathological embryos. The main results were the following: both beverages applied influenced the preimplantation development; with respect to the developmental rate and to the induction of pathological changes, the effect of both beverages was similar (retardation and an increased, number of pathological morulae and blastocysts); a different action could be detected as to the mean litter size and to the migration of preimplantation embryos: plum-brandy reduced more substantially the mean litter size, whereas cognac had a more marked retarding effect upon the migration of embryos from the oviduct to the uterus: all the changes detected show a more or less marked "litter-effect". The present data were compared with the corresponding effects of chronic ethanol administration observed previously in our laboratory. No obvious potentiating effect of beverage congeners could be established. The findings are discussed in connection with other experimental models of alcohol embryo and fetopathy.     

The effect of ethanol upon early development in mice and rats. XIV. The effect of acute intoxication with beer and wine upon preimplantation development in rats

The preimplantation effect of acute intoxication during the preimplantation period of pregnancy (i.p. or i.v. injection on day 4) with beer and wine has been investigated on female albino rats (Wistar strain). The following criteria were applied for checking preimplantation development: mean number of embryos/animal; topographical distribution of the embryos; developmental stage attained; occurrence of pathological embryonic forms. The control on day 5 of pregnancy revealed no significant effect upon the developmental criteria used. The data obtained are compared with our own previous results.     

The effect of ethanol upon early development in mice and rats. II. In vitro effect upon early postimplantation rat embryos

The direct effect of ethanol upon in vitro cultured 9.5 day rat embryos was investigated (2, 4, 8 and 10% ethanol added to the culture medium). The main effects recorded were as follows: 1. Significant increase of the number of "dying" embryos (beating heart without yolk sac circulation); 2. No significant increase of mortality; 3. Significant increase of the number of living embryos with deficient blood circulation; 4. Significant retardation of coiling in living embryos with a significant dose-effect relation, when the effects of 20/00 and 80/00 ethanol were compared; 5. Lowering of the mean somite number in living embryos; 6. Various macro- and macroscopical pathological changes (mainly necrotic areas in the central nervous system).     

The effect of ethanol upon early development in mice and rats. IV. The effect of acute ethanol intoxication of day 4 of pregnancy upon implantation and early postimplantation development in mice

Acute ethanol intoxication in albino mice (RAP) induced by intravenous administration of ethanol on day 4 of pregnancy delayed or inhibited implantation in about 25 per cent of the cases. The noxious action upon the implantation process showed a clear-cut "litter effect" and the mean litter was not affected by the experimental intervention. In very early postimplantation stage (day 6 of pregnancy) a statistically significant advance of some main morphogenetic indices was detected in treated specimens. As a possible explanation of this finding, a "selection" of more resistant and viable embryos by the acute ethanol intoxication is presumed. The data discussed in the present paper, together with authors' previous findings suggest a possible noxious action of acute ethanol intoxication during preimplantation stages upon implantation.     

In vivo studies of ethanol on prolactin and luteinizing hormone in rats and mice

The interaction of ethanol (EtOH), prolactin (Prl) and luteinizing hormone (LH) was examined in two studies. In the first study, adult male C57 B1/6J mice were given a single intraperitoneal injection of either vehicle or Prl at 5, 10 and 20 mg/kg and a significant dose-related suppression of ethanol consumption was found. This injection did not cause any differences in food intake or body weight. Additionally, a 5 mg/kg dose of Prl was also given to adult male Long Evans Hooded rats and, similarly, there was a significant suppression of ethanol consumption. In a second study, when rats were given a free choice between water and 5% EtOH, three subgroups were found regarding the amount of EtOH consumption: low, medium and high. After 2 weeks of free choice, hypothalamic, but not serum Prl and LH levels, were significantly increased in EtOH-imbibing groups compared to controls. These findings suggest important interactions between EtOH consumption and ambient levels of Prl and LH.     

In vivo nephrotoxicity induced in mice by chromium(VI)

The role of glutathione (GSH) and chromium (V) in chromium (VI)-induced nephrotoxicity in mice was investigated at 24 h after K2Cr(VI)2O7 ip injection. Nephrotoxicity was assessed by measurements of relative kidney weight and serum urea nitrogen. Cr(VI) nephrotoxicity was accompanied by decreased renal GSH and glutathione reductase (GSSG-R) levels. Pretreatment with buthionine sulfoximine, an inhibitor of GSH biosynthesis, enhanced Cr(VI)-induced nephrotoxicity, and remarkably diminished kidney GSH and GSSG-R levels. In contrast, pretreatment with glutathione methyl ester, a GSH-supplying agent, prevented Cr(VI) from exerting a harmful effect on mouse kidney and restored kidney GSH level. Administration of a Cr(V) compound, K3Cr(V)O8, induced much higher toxicity in mouse kidney than Cr(VI), but it failed to diminish renal GSH level. Another Cr(V) compound, Cr(V)-GSH complex, and Cr(III) nitrate did not cause a nephrotoxic effect in mice. The mechanism of Cr(VI)-induced nephrotoxicity was explained using GSH and Cr(V).     

Comparison of acetaldehyde and ethanol: depression of motor activity in mice

The fine and gross motor activity of mice was measured at 1-minute intervals for 15 minutes after intravenous administration of ethanol or acetaldehyde. Acetaldehyde transiently reduced both types of motor activity whereas the effects of ethanol were more prolonged. The 1-minute ED₅₀ values for depression of fine and gross activity by acetaldehyde are 2.2. and 2.7 mg/kg, respectively. The corresponding values for ethanol are 740 and 516 mg/kg. The differences in relative potencies became smaller as the time interval over which activity was measured increased. Thus, the potency of acetaldehyde as a depressant of behavior relative to ethanol is considerably greater than has previously been reported if effects are determined immediately after drug administration.     

The effect of chronic oral alcoholization upon late fetal development in mice

The late fetal effect of chronic alcoholization in two strains of mice (RAP and RAP female x CBAT6 male) was controlled. Unilateral ocular anomalies (retinal folding, various degrees of ocular disorganization) were detected in 16% of the alcoholized RAP female x CBAT6 male group. The findings are discussed in connection with other experimental models of alcohol embryo and fetopathy.