[Effect of angiotensin on the ultrastructure of the rat thyroid gland]. / Deistvie angiotenzina na ul'trastrukturu shchitovidnoi zhelezy krys.

Four hours after administering angiotensin to rats accumulation of radioactive iodine by the thyroid glands is inhibited. Angiotensin produces the contraction of thyroid arterioles. The cytoplasm of endotheliocytes of the perifollicular exchange microvessels becomes dense and luminar surfaces very involuted. Administration of angiotensin also leads to the changes in the ultrastructure of thyrocytes. The cisternae of the granular endoplasmic network get enlarged, the number of membrane-associated ribosome and mitochondria diminishes, that of lysosomes increases.

[Tissue basophils of the thyroid gland in developing amphibia and mammals]. / Tkanevye bazofily shchitovidnoi zhelezy razvivaiuschikhsia amfibii i mlekopitaiushchikh.

The number of mast cells has been established to increase sharply during the metamorphosis of Bufo viridis tadpoles and during the period of postnatal ontogenesis of rats. The data obtained are under discussion to represent mast cell as a system-forming element of thyroid microregion.

[Action of lysosomotropic modulators on the thyroid cells of rats]. / Deistvie lizosomotropnykh moduliatorov na kletki shchitovidnoi zhelezy krys.

Hydrocortisone, ammonium chloride, pepstatin and contrykal have been studied for their effect on incubated and cultured fragments of rat thyroid gland. It is found that the radioactive iodine uptake by thyroid gland cells is inhibited by hydrocortisone, ammonium chloride and pepstatin. Pepstatin induces formation of vacuoles with nonhydrolyzed thyroglobulin in thyrocytes.

[Effect of heparin on the thyroid gland]. / Vliianie geparina na shchitovidnuiu zhelezu.

Effect of heparin on the white rat thyroid gland has been studied in vivo and in vitro by means of light microscopy, electron microscopy and radiometry methods. Heparin is injected subcutaneously (1,000 units per 100 g of the body mass) once in 24 h. In the in vitro experiments heparin contents in medium is 10 units/ml and 10 units/ml. Heparin produces a decrease in thyrocyte height (control--12.6 +/- 0,5, experiment--10.4 +/- 0.6 mcm), a decrease in the number of folds on the basal surface of thyrocytes, changes in Golgi complex and an increase in electron density of the mitochondrial matrix. In endotheliocytes of the perifollicular blood capillaries the number of fenestrae decreases. Iodine accumulation in the thyroid is lowered under the effect of heparin. The thyroid gland blood stream (estimated by accumulation of 86Rb) decreases by 35%. The data obtained support the previous suggestion of the authors on a system-forming role of the tissue basophils in the thyroid micro-region.

[Effect of exogenic thyroid RNA on cultured fragments of the dog thyroid]. / Deistvie eksogennykh tireoidnykh RNK na kul'tiviruemye fragmenty shchitovidnykh zhelez sobak.

Radioactive iodine accumulation, protein and RNA synthesis by organic cultures of the dog thyroid gland after addition of exogenic thyroid RNA to the medium were studied. It was established that thyrotropin-induced exogenic RNA stimulates radioactive iodine accumulation as well as protein and RNA synthesis. The role of the thyrocyte genetic apparatus in throtropin mode of action is discussed.

[Comparative morphology of intercellular contacts]. / Sravnitel'naia morfologiia mezhkletochnykh kontaktov.

The data of the literature on ultrastructure of the intercellular contacts in main types of Metazoa (Spongia, Coelenterata, Plahelminthes, Annelides, Mollusca, Arthropods, Echinodermata and Chordata) have been analysed in view of systemic organology. Function of the intercellular contacts is considered as system-forming. Three aspects in the system-forming function of the intercellular contacts have been determined--adhesion, communication and isolation. Increase in the system-forming function of these structures has been demonstrated to be the main regularity in the evolution of the intercellular contacts in animals; this point is proved by analysing all the three aspects. A suggestion is made on the source for appearance of tight junctions.

[State of the rat thyroid gland in coarctation of the abdominal aorta]. / Sostoianie shchitovidnoi zhelezy krys pri koarktatsii briushnoi aorty.

In order to study connections between blood vessels and follicular thyrocytes, the method of modulation (a purposeful change of state in one element with registration of states in other elements of the system) was used. In rats chronic increase of blood stream was produced in the thyroid gland; in 15 days it was 54% as high as in the control. The volume of the vascular bed increased by 28% and that of follicles by 26%. Volumetric ratio between the thyroid epithelium and colloid did not changed. Follicular thyrocytes grew high and the nuclear volumes of these cells increased. Thyrocytes greately varied in their height. The number of mast cells in the thyroid gland remained the same. Iodine absorption by the thyroid gland increased as it is dependent on the volume of the vascular bed of the organism (+0.82). The data obtained demonstrate a significant connection existing between the follicular thyrocytes and blood vessels.