PubMed Health⌕ Search

Biomedical subjects

A Babický

Publications and source records attributed to A Babický.

At least 37 records · Page 2Linked to original sources
PubMed1986

Endogenous vasopressin and the weaning period in Brattleboro rats.

Vasopressin, which is important for behavior and brain development, begins to influence osmoregulation with the onset of weaning. We studied the role of vasopressin in the development of feeding behavior since its mechanisms might be essential for the age determination of the suckling and weaning periods. Radionuclide methods were employed to follow maternal milk, solid food and water consumption in developing Brattleboro rats. The appearance of solid food intake and the spontaneous extinction of maternal milk intake indicated the onset and the end of weaning. The absence of endogenous vasopressin did not influence the onset and/or the duration of the weaning period. Both vasopressin-deficient homozygous Brattleboro rats and their heterozygous littermates (with preserved vasopressin synthesis) began to consume solid food and water at the age of 16 days and their intake of maternal milk was terminated about the 27th day of age. Thus, the maturation of feeding behavior in the suckling and weaning periods is vasopressin-independent.

Animals↗
PubMed1986

Protein malnutrition of the lactating female rat: effect on maternal behaviour and spontaneous weaning of young rats.

Female rats were kept on a diet with a low content of animal protein (5.5%) beginning from the 2nd day after delivery. Beginning from the 10th day after delivery their body weight was persistently lower than that of control females. Also the body weight of their young was lower than that of control animals throughout the experiment, with significant differences appearing on the 17th day of life. Spontaneous termination of maternal milk intake occurred in malnourished young 10 days later than in the controls. Retention of 85Sr in malnourished females was in keeping with their milk production. Irrespective of the differences in body weight and the quality of solid food, the malnourished young began consuming solid food at the same age and in the same relative amounts as the controls. Thus in malnourished young the period of gradual weaning was prolonged by more than to 3 weeks in contrast to 2 weeks in the controls. This is probably due to the slower extinction of the oral sucking mechanism resulting from changes in the maturation of the CNS. No changes were found in maternal behaviour (nest building and efficiency of retrieving) in malnourished females during the suckling period. However, infanticide appeared in some females during the weaning period.

Animals↗
PubMed1985

Age dependence of selenite uptake in rat eye lenses.

75Se-selenite was administered to young and adult rats in subcutaneous injection or added into the medium in which eye lenses were incubated. The 75Se uptake in lenses of the young was significantly higher in comparison with adults both in vivo and in vitro. The in vivo 75Se uptake, referred to unit of lens weight, was almost 500 times higher in young animals while in vitro it was only five times higher, which apparently reflects the age-dependent differences in the structure and function of membranes and/or system barriers.

Aging↗
PubMed1985

Influence of thyroxine and propylthiouracil administration on the intake of maternal milk in sucklings of the laboratory rat.

Young laboratory rats received a daily subcutaneous injection of thyroxine (T4) and propylthiouracil (PTU) in saline, from birth until the period of spontaneous weaning. The rate of growth and the time of eye opening as well as the spontaneous weaning was assessed. The intake of maternal milk was followed directly, i.e. by the transport of 85Sr in maternal milk from the maternal body to the sucklings. In the young treated with T4 the eyes opened earlier than in the young treated with PTU. The body mass differed in both groups between the 4th and 20th day of life (the T4 pups were heavier). The 85Sr transfer in maternal milk was higher in the PTU young from the 22nd day of life. The PTU sucklings weaned spontaneously one week later than those receiving T4. A hypothesis has been proposed on the primary significance of maturation of oral mechanisms of sucking for spontaneous weaning.

Animal Population Groups↗
PubMed1984

Nutritional dependence of the incidence of selenite-induced cataracts in rats.

The protective effect of premature weaning on the incidence of selenite-induced cataracts in young rats can be abolished by the timely administration of the main components of nourishment, including water. The results suggest that water which is a common factor of all supplemented nutrients could play an important role in the development of selenium cataract.

Animals↗
PubMed1984

Effects of the withdrawal of solid food on maternal milk intake and the development of young rats.

Young rats deprived of solid food will survive on mother's milk only for about seven weeks but their development will become arrested completely. As soon as they receive solid food their development recommences immediately at the same rate as that of control infant rats. However, young rats still continue to take maternal milk for about one more week, which is the result of the gradual extinction of the sucking reflex depending the maturity of the young rats.

Animal Population Groups↗
PubMed1983

Delimitation of the period of sensitivity to the cataractogenic action of selenite in rats.

The period when selenite is able to induce cataracts begins on the 2nd and ends on the 17th day of postnatal life. Higher doses of selenite do not change the beginning of the cataractogenic period but may induce rare cataracts (up to 17%) when given on the 18th and 19th day of life. The lethal effect of selenite, which predominantly depends on the administered dose, is significantly lowered during the period of selenite-induced cataractogenesis.

Age Factors↗
PubMed1982

Ontogenic changes in selenite metabolism in rats.

Radioselenium concentration and excretion was studied after administration of 75SE-labelled selenite to male rats during ontogeny. The concentration of radioselenium in individual organs decreases with increasing age. The largest differences between young and adults were in the quantity and quality of excreted substances. During 2 h after the administration of 20 mumol selenite/kg young rats excreted 2.4% of the dose, essentially in the urine only, whilst adults excreted a total of 11%, distributed equally in breath and urine. The part excreted as methylated metabolites was 0.1% of the administered dose in young and 6.3% in adult rats. These results support the hypothesis that the differences in the sensitivity to the toxic action of selenite between young and adult rats can be due to ontogenic differences in selenium metabolism.

Aging↗