[AGE AND SEX FEATURES OF BONE MINERAL DENSITY IN RATS].

In vivo assessment of bone mineral density (BMD) and bone mineral content (BMC) indices gives an objective description of the possible rates of bone loss during aging and various diseases, as well as response to treatment by various drugs, affecting bone metabolism. This study was conducted on 376 Wistar rats of both genders, divided into 12 age groups using the method of dual-energy X-ray absorptiometry. Studying the parameters of BMD and BMC depending on age and sex has found no bone mass opeak) in rats of both sexes.

[Characteristics of heritability and effect of selection on prevalence of diffuse-toxic goiter in population].

On genealogic data about 242 Gravers disease patients, fertility parameters of 2105 healthy and 369 Grave's disease women peculiarities of genetic determination and natural selection of disease were studied. Results of the genetic analysis have revealed conformity of Grave's disease inheritance to alternative model parameters. Homozygote penetrance within the framework of this model was 78.

[Effect of peptide regulators on the structural and functional status of bone tissue in ageing rats].

The wide spread of osteoporosis in women in the post-menopausal period stipulates the need for new effective means of prevention and correction of pathologic alterations in the bone tissue. Effect of two peptide bioregulators: cartilages preparation based on the cartilaginous tissue extract and T-31 substance on the mineral density of rat bone tissue has been studied in the experimental model of osteoporosis. The study has revealed an osteoprotective effect of both studied substances, with significantly higher efficacy of the preparation based on cartilaginous tissue extract.

[Effect of thyroid hormones on calcitonin secretion].

A study of 140 patients with diffuse toxic goiter showed phasic change in plasma calcitonin concentration and blood calcitonin activity: an increase in these indices at early stages of disease with a subsequent decrease in a severe form of thyrotoxicosis. Basal calcitonin secretion by fragments of the thyrotoxic thyroid was much higher than that euthyroid gland. In incubation of paranodal tissue of the thyroid of patients with nodular euthyroid goiter and fragments of the thyroid of patients with thyrotoxicosis of moderate severity with thyroxin at concentration 10(-8) M the level of calcitonin secretion considerably increased, concentration 10(-6) M was ineffective.