RESUMEN
To investigate combined effects of stress and metal (aluminium, cadmium) on reproductivity, male rats twice per week received intraperitoneal injections of aluminium (3.8 mg Al3+ per kg of body weight) or cadmium (0.3 mg Cd2+ per kg of body weight) and were subjected to stress via short-term immobilization during spermatogenic cycle (54 +/- 3 days). Findings are cumulation of both cadmium and aluminium in genitals and brain, increasing under stress. When acting separately to the laboratory animals, the three factors (aluminium/cadmium/stress) increase serum corticosterone level, change testosterone level, increase number of aberrant mitoses of spermatogenic epithelium cells, increased sperm count with fragmented DNA, lower percentage of the impregnated females. If the exposure combined with stress, spermatogenesis disorders are more marked, and preimplantation death rate of intact females' offspirngs becomes statistically significant.
Asunto(s)
Aluminio/toxicidad , Cadmio/toxicidad , Reproducción/efectos de los fármacos , Estrés Psicológico/fisiopatología , Aluminio/sangre , Aluminio/farmacocinética , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Cadmio/sangre , Cadmio/farmacocinética , Aberraciones Cromosómicas/inducido químicamente , Corticosterona/sangre , Fragmentación del ADN/efectos de los fármacos , Pérdida del Embrión/inducido químicamente , Pérdida del Embrión/genética , Femenino , Masculino , Embarazo , Ratas , Ratas Wistar , Restricción Física , Espermatogénesis/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Espermatozoides/patología , Estrés Psicológico/metabolismo , Estrés Psicológico/patología , Testículo/efectos de los fármacos , Testículo/metabolismo , Testículo/patologíaRESUMEN
The evaluation of the isolated and combined effects of aluminum and immobilization stress on the reproductive system of male laboratory rats has been performed. We have established the influence of these factors on spermatogenesis and spermiogenesis: the development of degenerative processes in the testes, on specific hormonal status, apoptosis, increasing abnormal forms of epididymal sperms and reducing their mobility, and on the growth of early embryonic losses. Neither synergistic nor antagonistic effect in the combined aluminum and the stress action has been found.
Asunto(s)
Compuestos de Aluminio , Nitratos , Reproducción/efectos de los fármacos , Espermatogénesis/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Estrés Fisiológico , Compuestos de Aluminio/administración & dosificación , Compuestos de Aluminio/farmacocinética , Compuestos de Aluminio/toxicidad , Animales , Modelos Animales de Enfermedad , Femenino , Inyecciones Intraperitoneales , Masculino , Nitratos/administración & dosificación , Nitratos/farmacocinética , Nitratos/toxicidad , Ratas , Ratas Wistar , Restricción Física , Bloqueadores de Espermatogénesis/administración & dosificación , Bloqueadores de Espermatogénesis/farmacocinética , Bloqueadores de Espermatogénesis/toxicidad , Teratógenos/farmacocinética , Teratógenos/toxicidadAsunto(s)
Sedimentos Geológicos/microbiología , Metano/metabolismo , Methylococcaceae/fisiología , Microbiología del Suelo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Dióxido de Carbono/metabolismo , Frío , Methylococcaceae/genética , Oxidación-Reducción , Oxigenasas/genética , Oxigenasas/metabolismo , Reacción en Cadena de la Polimerasa , Siberia , TemperaturaRESUMEN
The PCR analysis of DNA extracted from soil samples taken in Russian northern taiga and subarctic tundra showed that the DNA extracts contain genes specific to methanotrophic bacteria, i.e., the mmoX gene encoding the conserved alpha-subunit of the hydroxylase component of soluble methane monooxygenase, the pmoA gene encoding the alpha-subunit of particulate methane monooxygenase, and the mxaF gene encoding the alpha-subunit of methanol dehydrogenase. PCR analysis with group-specific primers also showed that methanotrophic bacteria in the northern taiga and subarctic tundra soils are essentially represented by the type I genera Methylobacter, Methylomonas, Methylosphaera, and Methylomicrobium and that some soil samples contain type II methanotrophs close to members of the genera Methylosinus and Methylocystis. The electron microscopic examination of enrichment cultures obtained from the soil samples confirmed the presence of methanotrophic bacteria in the ecosystems studied and showed that the methanotrophs contain only small amounts of intracytoplasmic membranes.
