[Cellular-differon organization of vaginal wall muscular tissues in mammals].

Complex histological analysis of vaginal wall muscular tissues was carried out in several species of laboratory animals (mature rats, cats, dogs) and humans. The muscular tunic of vaginal wall was found to be represented by two types of tissue: striated and smooth muscle. Striated muscular tissue of vagina has specific features and consists of two cellular differons: myosymplasts and satellite cells. The smooth muscular tissue is formed by a single cellular differon, in which undifferentiated, differentiating and differentiated cells could be distinguished. Phenotypically, within vaginal smooth muscular tissue, contractile and contractile-secretory smooth myocytes were demonstrated.

[Histogenesis and structural organization of the walls of rat venae cavae and pulmonary veins]. / Gistogenez i strukturnaia organizatsiia stenki polykh i legochnykh ven krysy.

Using light and electron microscopic methods, the histogenesis and structural organization of the walls of rat venae cavae and pulmonary veins were studied in prenatal and postnatal periods of development. The special attention was paid to the appearance of the striated myocytes in the walls of these vessels during the process of ontogenesis. The time of initial divergent development of myoblastic differon was established, the stages of differentiation of striated myoblasts and the peculiarities of intercellular junctions were characterized, as well as the innervation and vascularization of the walls of venae cavae and pulmonary veins.

[Cardiomyogenesis in Rana ridibunda tadpoles during metamorphosis in normal conditions and after exposure to various concentrations of cadmium ions]. / Kardiomiogenez u ozernoi liagushki v period metamorfoza golovastikov v norme i pri vozdeistvii ionov kadmiia v razlichnykh kontsentratsiiakh.

During metamorphosis period Rana ridibunda ventricular cardiomyocytes possess strong ability to adapt to altering developmental conditions, certain peculiarities of differentiation were observed during this process, cell death and mitotic activity increases. The action of different concentrations of cadmium ions on Rana ridibunda larvae changes interrelation and intensity of basic processes of cardiac muscular histogenesis, leading to differentiation disorders, suppression of proliferative activity and intensification of cardiomyocytes death.

[Death of myocardiocytes and destruction of their structures during embryonic histogenesis]. / Gibel' kardiomiotsitov i razrushenie ikh struktur v émbrional'nom gistogeneze.

By means of light and electron microscopy, death of cardiomyocytes and their structures has been studied in the myocardium of chick (the 4th-20th days of incubation) and in rat (the 14th-20th days of embryogenesis) embryos. The same processes have been studied after a single and repeated injections of insulin and 5-fluorauracyl to the chick embryos (into the air chamber of the egg). In the myocardium of the chick and rat embryos atrophy of some muscle cells takes place as a demonstration of histogenetic (physiological) death characterized by changes in nucleo- and cytoplasm according to the "dark" type. Under the effect of 5-fluorauracyl the same type of cardiomyocyte death is observed; differences with the control are but quantitative ones. When the chick embryo is affected with cytotoxic concentrations of insulin, together with histogenetic death of the cardiomyocytes (the "dark" type) the death according to the "light" type also takes place. Under the effect of both insulin and 5-fluorauracyl the destructive processes in the cardiomyocytes are manifested greater than in the control. This is a morphological manifestation of certain disturbances in processes of physiological restoration at the cellular level.

[Myocardial regeneration in chick embryos after cyclophosphane exposure]. / Regeneratsiia miokarda émbrionov kur posle vozdeistviia tsiklofosfanom.

By means of light and electron microscopy, radioautography, regeneration of the chick embryo myocardium has been studied at metabolic lesions produced with cyclophosphamide injection into the egg air chamber on the 4th day of incubation. Certain destructive processes in cardiomyoblasts, increased cellular death, decreased activity of DNA synthesis and mitotic activity of the cardiac muscular cells are noted. Two-four days after cyclophosphamide injection, ultrastructure of the cardiomyoblasts is restorted, as well as their DNA synthesis is normalized. The mitotic activity is higher than the control one. Restorative processes in the chick embryo myocardium take place at the expense of the intracellular regeneration occurring together with the mitotic division of the cardiac muscular cells.

[Ultrastructural analysis of reactive changes in the myocardium upon embryo exposure to an alkylating agent]. / Ul'trastrukturnyi analiz reaktivnykh izmenenii miokarda pri vozdeistvii na zarodysh al'teriruiushchego agenta.

Subcellular reaction of certain structural components in the chick embryo myocardium to a single dose of the alkylating cyclophosphamide compound has been studied electron microscopically. It has been stated that the muscle cell edema, desorganization of the intracellular organells, reactions of the lysosomal apparatus occur in the myocardium. Two types of the cardiac muscle cell edema are revealed: 1) without any disturbance in intracellular organells; 2) with their advanced desorganization. Cells in the capillary endothelium are affected simultaneously to the muscle cells of the myocardium. Regenerative processes result in normalization of ultramicroscopical structure of the muscle cells. The subcellular reaction of the embryonal myocardium is characterized by a rapid course of the destructive and regenerative processes.