RESUMEN
The teratogenic effects of the coadministration of alcohol and cocaine on gestation days 14-17 were investigated using an acute exposure model. Pregnant C57BL/6J mice were assigned randomly to treatment groups generated from a 2 (0 or 6 g/kg alcohol) x 2 (0 or 60 mg/kg cocaine) x 4 (day of treatment) factorial design. An untreated control group was also employed. On GD14, 15, 16, or 17, females were intubated with alcohol or an isocaloric solution and injected (SC) 10 min later with cocaine or saline. Litters were evaluated on GD19 following cesarean delivery. A significant number of females in the alcohol-only group treated on GD16 or GD17 delivered litters prior to GD19. The results indicated that, in general, prenatal alcohol exposure was associated with decreased fetal body weight and suggested a possible increase in malformations of vascular origin. Cocaine and the alcohol/cocaine interaction did not affect the outcome variables in any reliable manner. Thus, with the animal model employed, cocaine did not exert teratogenic effects on its own nor did it influence alcohol-induced teratogenesis.
Asunto(s)
Anomalías Inducidas por Medicamentos , Cocaína/toxicidad , Etanol/toxicidad , Edad Gestacional , Animales , Peso Corporal , Cocaína/administración & dosificación , Etanol/administración & dosificación , Etanol/sangre , Femenino , Muerte Fetal , Hematoma/inducido químicamente , Masculino , Ratones , Ratones Endogámicos C57BL , Trabajo de Parto Prematuro , Embarazo , Razón de Masculinidad , Aumento de PesoRESUMEN
The teratogenic effects of cocaine and ethanol were investigated using an acute treatment model of C57BL/6J mice treated on gestation day 15 (GD15) with evaluation on GD17. Females were intubated once with a subteratogenic dose of ethanol (0 or 4 g/kg) and injected subcutaneously twice, 1 h apart, with equal doses of cocaine HCl (0 or 60 mg/kg), for a final daily dose of 120 mg/kg. The first cocaine injection followed ethanol by 10 min. Blood ethanol levels (BEL) and plasma cocaine levels were determined, and pair-feeding was employed. The results revealed no group differences on pregnancy outcome. That is, maternal weight gain, total number of implants, prenatal mortality, and fetal body weight were not statistically different. No significant differences in BEL or plasma cocaine levels were found among the various treatment groups. These results suggest that, under these conditions, relatively high levels of cocaine (120 mg/kg, SC), given alone or in combination with subteratogenic doses of ethanol late in pregnancy, are not teratogenic in mice.
Asunto(s)
Cocaína/toxicidad , Etanol/toxicidad , Muerte Fetal , Intercambio Materno-Fetal , Animales , Desarrollo Embrionario y Fetal/efectos de los fármacos , Femenino , Edad Gestacional , Tamaño de la Camada/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Embarazo , Resultado del Embarazo , Aumento de Peso/efectos de los fármacosRESUMEN
Species differences in selectivity with respect to mate choice have been hypothesized to be related to mating systems. Procedures used in 3 previous experiments on monogamous prairie voles (Microtus ochrogaster) and polygamous montane voles (M. montanus) were used with polygamous meadow voles (M. pennsylvanicus). The expectation was that meadow voles would show few preferences. Female meadow voles preferred mating with familiar versus unfamiliar males but displayed no preference for unmated versus mated males. Male meadow voles displayed no preference for unmated versus mated females. The results are partially consistent with the hypothesis that relates mate choice to social and mating system, as this polygamous species resembles polygamous montane voles species in 2 situations but is similar to monogamous prairie voles in the 3rd.
Asunto(s)
Arvicolinae/psicología , Conducta Sexual Animal , Animales , Conducta de Elección , Copulación , Estro/psicología , Femenino , Masculino , Conducta Social , Medio SocialRESUMEN
Patterns of nipple attachment and incisor growth were compared between four species of voles (Microtus). Offspring of two highly social species, prairie voles (M. ochrogaster) and pine voles (M. pinetorum), were shown to cling tightly to the nipples of their dams on Days 2, 6, and 10. This pattern contrasted to weak nipple attachment displayed by two less-social species, meadow voles (M. pennsylvanicus) and montane voles (M. montanus). Lengths of the upper (maxillary) and lower (mandibular) incisors of the four species were recorded throughout the first 10 days of age and in adults. Incisors of the pine and prairie voles typically erupted earlier and grew longer than those of the meadow or montane voles during the first few days of development. Incisors grew at a substantial rate in the latter two species, such that they equalled or surpassed the incisor lengths of the former two species as Day 10 and weaning approached. Patterns of incisor growth, in part, reflected those for nipple attachment, but do not appear to account substantially for differences in nipple attachment.
Asunto(s)
Incisivo/crecimiento & desarrollo , Conducta en la Lactancia/fisiología , Animales , Arvicolinae/crecimiento & desarrollo , Peso Corporal/fisiología , Femenino , Tamaño de la Camada , Masculino , Especificidad de la EspecieRESUMEN
The teratogenic effects of the coadministration of alcohol (ethanol) and cocaine to pregnant C57BL/6J mice were investigated using an acute treatment model on gestation day 10 (GD10). The day of mating was designated as GD1. Pregnant mice were assigned to treatment groups generated from a 3(0, 4, 6 g/kg alcohol) x 3 (0, 40, 60 mg/kg cocaine) factorial design to explore possible interactive effects of these commonly abused drugs. Females were treated on GD10 (alcohol gavage followed by SC cocaine injection) and their litters were evaluated on GD19 by cesarean delivery. Two additional free-fed groups, as well as a pair-fed group, were employed. Food and water intake was recorded in treated groups. Results indicated that only the high dose alcohol produced a significant decrease in fetal body weight and a significant elevation of the incidence of kidney and limb malformations. These effects could not be attributed to restricted food intake. Cocaine was not found to produce any significant perturbations of development, either alone or in combination with alcohol. These results suggest that acute prenatal cocaine exposure on GD10 does not produce teratogenic effects when administered alone or in combination with acute alcohol in C57BL/6J mice, at least under the present experimental conditions.
Asunto(s)
Cocaína/toxicidad , Etanol/toxicidad , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/patología , Animales , Peso Corporal/efectos de los fármacos , Cocaína/análogos & derivados , Cocaína/sangre , Inhibidores de Captación de Dopamina/sangre , Interacciones Farmacológicas , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Alimentos/fisiología , Etanol/sangre , Femenino , Feto/patología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Embarazo , Resultado del EmbarazoRESUMEN
A gas chromatographic-mass spectrometric method is described for the determination of cocaine and ethylcocaine (cocaethylene) from mouse plasma microsamples (50 microliters). [2H3]Cocaine and [2H5]ethylcocaine served as internal standards, analytical separations were performed on a (5% phenyl)methylpolysiloxane capillary column, and detection was by selected-ion monitoring of electron-impact generated fragment ions [M - CO2Ph]. Pilot study plasma concentrations of ethylcocaine following coadministration of cocaine and ethanol were less than 5% of the parent drug.
Asunto(s)
Cocaína/análogos & derivados , Cocaína/sangre , Inhibidores de Captación de Dopamina/sangre , Animales , Cocaína/síntesis química , Deuterio/análisis , Inhibidores de Captación de Dopamina/química , Femenino , Cromatografía de Gases y Espectrometría de Masas , Marcaje Isotópico , Ratones , Ratones Endogámicos C57BL , Estándares de ReferenciaRESUMEN
Data were collected on the huddling behavior of pine voles, Microtus pinetorum, and meadow voles, M. pennsylvanicus, to supplement earlier data on prairie voles and montane voles. Species that are social/monogamous in the field tended to huddle more in the laboratory. Contact proneness may be one factor driving different mating systems in the field.
Asunto(s)
Arvicolinae/psicología , Conducta Social , Medio Social , Animales , Femenino , Masculino , Conducta Sexual Animal , Especificidad de la EspecieRESUMEN
Male-induced estrus was examined in montane (Microtus montanus), meadow (M. pennsylvanicus), prairie (M. ochrogaster), and pine (M. pinetorum) voles. Duration of male contact needed for receptivity, effects of parity, and vaginal cytology were assessed. Among nulliparous females, montane voles attained receptivity with less male contact than prairie voles. Meadow and pine voles showed very low receptivity rates. Among parous females, montane and meadow voles did not differ in duration of male contact needed for receptivity and required less than prairie voles. Overall, parous females had higher receptivity rates than nulliparous females. When isolated from males, prairie and pine voles had more leukocytes and fewer cornified cells in vaginal smears than montane or meadow voles. Species differences in estrus induction are discussed in relation to species differences in social organization.
Asunto(s)
Arvicolinae/fisiología , Estro/fisiología , Medio Social , Animales , Copulación/fisiología , Femenino , Masculino , Especificidad de la Especie , Vagina/fisiologíaRESUMEN
This study was designed to determine testes masses, total number of spermatozoa ejaculated per copulatory episode, and the pattern of sperm numbers in successive ejaculates in prairie voles (Microtus ochrogaster), montane voles (M. montanus), pine voles (M. pinetorum), and meadow voles (M. pennsylvanicus). Prairie voles displayed mean totals of 2.7 ejaculations and 30.5 X 10(6) spermatozoa before reaching a satiety criterion; montane voles 3.4 ejaculations and 19.0 X 10(6) spermatozoa, pine voles 2.4 ejaculations and 3.3 X 10(6) spermatozoa, and meadow voles 2.5 ejaculations and 25.5 X 10(6) spermatozoa. In all species the number of spermatozoa decreased in successive ejaculates. Significant species differences were noted for the total number of spermatozoa ejaculated and number of spermatozoa ejaculated in each of the first 3 ejaculates. Species differences also were noted for testes mass, with meadow voles having the largest testes and pine voles having the smallest. These data can be compared to similar data on laboratory rats and deer mice and related to recent theory regarding sperm numbers, testes sizes, and mating systems. In general, the species with large testes appear to ejaculate more spermatozoa. The significance of species differences in testes mass and total sperm numbers remains unclear, but may relate to the occurrence of multiple mating by females during a single receptive period.