Asunto(s)
alfa 1-Antitripsina/genética , Animales , Animales Modificados Genéticamente , Clonación Molecular , ADN Complementario , ADN Recombinante , Escherichia coli/genética , Femenino , Humanos , Masculino , Metalotioneína/genética , Microinyecciones , Hibridación de Ácido Nucleico , Regiones Promotoras Genéticas , RatasRESUMEN
Against the background of the induced iron deficit ethanol (6.4 g/kg) causes aggravation of the embryolethal effect and anomalies in 15% of embryos in 14-day pregnant rats. Changes in the genome of rat males and females after the injection of the plasmid with a foreign gene at the stage of two pronuclei and the subsequent crossing with intact animals account for the increase in sensitivity of embryos to subteratogenic doses of sodium salicilate. The maternal organism disturbances have a more pronounced effect than the paternal ones.
Asunto(s)
Anomalías Inducidas por Medicamentos/genética , Embrión de Mamíferos/efectos de los fármacos , 2,2'-Dipiridil/administración & dosificación , Anomalías Inducidas por Medicamentos/etiología , Anemia Ferropénica/inducido químicamente , Anemia Ferropénica/complicaciones , Anemia Ferropénica/genética , Animales , Etanol/toxicidad , Femenino , Genoma , Genotipo , Masculino , Plásmidos/administración & dosificación , Embarazo , Complicaciones del Embarazo/etiología , Ratas , Salicilato de Sodio/toxicidadRESUMEN
An immunocytochemical analysis of hormonal status of transgenic rats containing human growth hormone gene has been done. The enhanced expression of the endogenous growth hormone gene was demonstrated with poly- and monoclonal antibodies inside somatatropes of pituitary. No activity of the heterologous growth hormone gene was revealed in kidney, pancreas or liver as it might be expected according to specificity of MT1 and TAT promotors. Transgenic animals of F0, F1 and F2 generation exhibited disturbance of functional morphology of glucagon and insulin producing cells. Lymphocyte infiltration was found in pancreatic islets. The transgenic rabbits and swine with the gene of releasing factor of human growth hormone did not reveal any severe disturbance. Although one swine demonstrated alterations in glucagon producing cells and one rabbit revealed a disturbed morphology of the stomach tissues. The data are discussed in relation to general problems of transgene activity and interaction with endogenous homolog.
Asunto(s)
Hormona Liberadora de Hormona del Crecimiento/metabolismo , Hormona del Crecimiento/metabolismo , Animales , Animales Modificados Genéticamente , Regulación de la Expresión Génica , Hormona del Crecimiento/genética , Hormona Liberadora de Hormona del Crecimiento/genética , Humanos , Inmunohistoquímica , Especificidad de Órganos , Hipófisis/metabolismo , Conejos , Ratas , Especificidad de la Especie , PorcinosRESUMEN
H-thymidine was injected into cytoplasm of the eggs taken at different intervals after fertilization and the eggs were fixed immediately thereafter. DNA synthesis was shown to begin in pronuclei when they are still in the marginal zones of cytoplasm, immediately after their formation. S-phase lasts 5-6 h in every pronucleus and is terminated at 1-2 h before the first cleavage division when the pronuclei are closely approached and located in the center of cytoplasm. At the end of S-phase late replicating heterochromatic regions are distinctly localized near the nuclear envelope and in pronuclei. Male and female pronuclei display asynchrony in the course of S-phase and differences in 3H-thymidine incorporation into chromatin. Structural features of the first cell cycle in mouse embryogenesis are discussed.
Asunto(s)
Citoplasma/metabolismo , Replicación del ADN , ADN/biosíntesis , Ratones/embriología , Timidina/metabolismo , Cigoto/metabolismo , Animales , Autorradiografía , Femenino , Histocitoquímica , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Microinyecciones , Profase , Timidina/administración & dosificación , Factores de Tiempo , TritioRESUMEN
The human growth hormone gene, containing mouse metallothionein gene promotor, was injected into the male pronuclei of fertilized mouse ova. The progeny of transgenic mice included animals with both accelerated and inhibited growth. Radioimmunochemical analysis has revealed human growth hormone synthesis in both groups of transgenic mice. The molecular weight of the hormone synthesized in liver cells was 25,000 daltons. A possible mechanisms of foreign hormone effect on the growth of transgenic mice is discussed.
Asunto(s)
Regulación de la Expresión Génica , Ingeniería Genética , Hormona del Crecimiento/genética , Crecimiento , Animales , ADN/genética , Femenino , Humanos , Masculino , Metalotioneína/genética , Ratones , Microinyecciones , Regiones Promotoras Genéticas , Transformación GenéticaRESUMEN
The fertilized mouse eggs obtained after the hormonal stimulation of the females were denuded by pronase and incubated for 1 h at 37 degrees in the culture medium with cytochalasin B (5 micrograms/ml) and, then, centrifuged 20 min (12,000 g) at ca. 31 degrees in Ficoll gradient added with cytochalasin B. Under these conditions the eggs were divided in anuclear (cytoplasts) and nuclear (karyoplasts) fragments. The cytoplasts kept their shape and ability for protein synthesis during cultivation and the karyoplasts performed one cell division. The viable cyto- and karyoplasts obtained from the eggs may be used in the experiments on cell hybridization and production of embryos-cybrids.
Asunto(s)
Núcleo Celular/ultraestructura , Cigoto/citología , Animales , Fraccionamiento Celular , Fusión Celular , Separación Celular , Supervivencia Celular , Centrifugación por Gradiente de Densidad/métodos , Citocalasina B/farmacología , Femenino , Ficoll , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Cigoto/efectos de los fármacosRESUMEN
The rat embryos at the stage of 8 blastomeres were explanted in the Biggers' medium with 20% of blood serum from the rats obtained different doses of aminopterin. The marked delay of cleavage rate, morphological anomalies of blastocysts, selective damaging effect of aminopterin upon the inner cells mass (embryoblast) and high resistance of trophectoderm cells against this drug were observed. The role of dihydrololate reductase at the preimplantation developmental stages, the resistance against aminopterin of the early rat embryos within the maternal organism and high sensitivity to this drug of the embryos in vitro are discussed. A conclusion is drawn on the presence of the barrier function of oviducts with respect to aminopterin.
Asunto(s)
Aminopterina/farmacología , Desarrollo Embrionario/efectos de los fármacos , Trompas Uterinas/metabolismo , Intercambio Materno-Fetal , Preñez/efectos de los fármacos , Aminopterina/metabolismo , Animales , Transporte Biológico , Blastocisto/efectos de los fármacos , Sangre , Relación Dosis-Respuesta a Droga , Femenino , Técnicas In Vitro , Mitosis/efectos de los fármacos , Embarazo , RatasRESUMEN
A study was made of antifolic preparation chloridine (2,4-diamino-5-p-chlorphenyl-6-ethylpyrimidine) on the cleavage of CBA mouse embryos. Chloridine failed to influence the development of early mouse embryos in the maternal organism and considerably inhibited the cleavage of embryos explanted into the chloridine-containing medium. Chloridine sensitivity in the mouse and rat embryos was compared and a conclusion was drawn on the absence of interspecies differences in their reaction to teratogen at the level of the embryonic cells.
Asunto(s)
Embrión de Mamíferos/efectos de los fármacos , Pirimetamina/farmacología , Teratógenos/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , Técnicas de Cultivo , Femenino , Ratones , Embarazo , Pirimetamina/administración & dosificación , Cigoto/efectos de los fármacosRESUMEN
A study was made of the dynamics of pathohistological changes occurring in the embryos of albino rats under conditions of a single action of teratogenic doses of daraprim of the 9th day of pregnancy. Decidual tissue proved to be the most sensitive to daraprim the first disturbances in this tissue were noted to soon as one hour after the injection. Cells of various embryonic tissues reacted to daraprim differently. Most pronounced cytotoxic effect of daraprim is seen on the embryonic mesoderm and on the extraembryonic ectoderm. A conclusion was drawn on a significant role played by hemodynamic changes associated with disturbances of decidual tissue in the mechanism of the pathogenic action of some chemical teratogens on mammalian embryos.
Asunto(s)
Anomalías Inducidas por Medicamentos/embriología , Pirimetamina , Animales , Decidua/patología , Femenino , Embarazo , RatasRESUMEN
DNA synthesis in the decidual tissue of rats on the 9-10th day of pregnancy has been studied in intact rats and under the effect of chloridin by means of radioautography and biochemical methods. The decidual cells of antimesometral and mesometral regions were shown to differ both by morphological features and intensity of 3H-thymidine utilization and activity of thymidylate synthetase and thymidine kinase. Under the conditions of the block of dihydropholate reductase, differences between the antimesometral and mesometral regions of deciduoma manifest themselves still more markedly. The decidual tissue consists of a heterogenous population of cells which differ by the ratio of different ways of thymidylate synthesis. An estimate is given for the ratio of two ways of thymidine monophosphate synthesis in the antimesometral regions of the decidual tissue.