Results 131 to 140 of about 805 (182)
Some of the next articles are maybe not open access.
Angiotensin converting enzyme in the toad Bufo arenarum
Comparative Biochemistry and Physiology Part A: Physiology, 1986Angiotensin converting enzyme activity (ACEA) was determined in serum, kidney, whole skin and isolated epithelia homogenates of the South American toad Bufo arenarum. ACEA was present in the tissues and serum of the toad. The activity was higher in the kidney, as compared to that of the whole skin or isolated epithelium.
J, Fernandez-Pardal +3 more
openaire +2 more sources
Metallothioneins and cadmium uptake by the liver in Bufo arenarum
Environmental Pollution, 1997Bufo arenarum females were treated daily with 0.5 mg Cd kg(-1) during 10 days to evaluate the uptake of this heavy metal and the induction of metallothionein synthesis in the liver. The liver incorporated 26% of the Cd administered, about 6.5 times higher than the average uptake of the other tissues of B. arenarum.
C S, Pérez-Coll +4 more
openaire +2 more sources
Pregnenolone and progesterone metabolism by the testes of Bufo arenarum
Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology, 1998Sliced testis tissue from Bufo arenarum was incubated in the presence of [3H]pregnenolone. Testis fragments were also used for double isotope experiments using [3H]pregnenolone and [14C]progesterone. Specific activities were equated with the addition of radioinert pregnenolone. When yields of radiometabolites were analysed, pregnenolone was found to be
L F, Canosa, A G, Pozzi, N R, Ceballos
openaire +2 more sources
Embryotoxicity of lead onBufo arenarum
Bulletin of Environmental Contamination and Toxicology, 1988Lead, one of the oldest and more widely distributed pollutants, produces serious toxicological effects. From an ecotoxicological point of view, amphibians are useful as indicators of environmental contamination because they are sensitive to a great variety of toxic agents.
C S, Pérez-Coll +2 more
openaire +2 more sources
Stage-Dependent Uptake of Cadmium by Bufo arenarum Embryos
Bulletin of Environmental Contamination and Toxicology, 1996Over the last several years, environmental contamination with cadmium has significantly increased because of its extensive use In anthropogenic activities. This heavy metal is a very toxic xenobiotic producing reproductive and developmental impairments in a wide spectrum of organisms. Within the life cycle of organisms, the embryo is the most sensitive
C S Pérez-Coll
exaly +3 more sources
Stage dependent susceptibility to lead in Bufo arenarum embryos
Environmental Pollution, 1990The stage dependent susceptibility to lead in amphibian development was studied by exposing Bufo arenarum embryos during neurulae, neuromuscular activity and gill circulation stages for twenty hours to 1 ppm Pb(2+). Survival, malformations and behavioral disorders were evaluated. The embryonic susceptibility to lead was markedly stage dependent.
C S, Pérez-Coll, J, Herkovits
openaire +2 more sources
Nuclear maturation inducers in Bufo arenarum oocytes
Zygote, 2001The present study analyses the effect of dihydrotestosterone (DHT) and mammalian insulin on the nuclear maturation of Bufo arenarum oocytes under in vitro conditions. The response of fully grown follicle oocytes to DHT, shown by germinal vesicle breakdown (GVBD), occurred in a manner dependent on dose, time and sexual cycle period.
I, Ramos +4 more
openaire +2 more sources
Characterization of a sexual steroid binding protein in Bufo arenarum
General and Comparative Endocrinology, 1985Reproductively active female Bufo arenarum possess a serum protein (SBP) that binds testosterone, dihydrotestosterone, and estradiol with high affinity and capacity. The binding capacity values are two orders of magnitude higher than those found in human serum. The specificity of B. arenarum SBP is comparable to human SBP with the exception that it has
T A, Santa-Coloma +2 more
openaire +2 more sources
Membrane currents in the oocyte of the toad Bufo arenarum
Journal of Experimental Zoology, 2002AbstractThe amphibian oocyte cell model is widely used for heterologous expression of ionic channels and receptors. Little is known, however, about the physiology of oocyte cell models other than Xenopus laevis. In this study, the two‐electrode voltage clamp technique was used to assess the most common electrical patterns of oocytes of the South ...
Basilio A, Kotsias +5 more
openaire +2 more sources
Evaluation of the Response of Bufo arenarum larvae to 20-Methylcholanthrene
Oncology, 2009We inoculated 214 animals with a 20-Methylcholanthrene suspension in olive oil. The first reaction, 3 to 9 days after inoculation, is an intensive epithelial hyperplasia with cellular disorientation, anisocytosis and increased mitotic activity limited to the site of inoculation.
Matos, Elena L. +1 more
openaire +3 more sources