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Biomedical subjects

Iu L Perov

Publications and source records attributed to Iu L Perov.

At least 37 records · Page 2Linked to original sources
PubMed1983

[Relation between the number of vesicles in the vascular smooth muscle cells and extracellular calcium concentration].

The relationship between the number of vesicles in smooth muscle cells in mesenterial arteries and calcium concentration in incubation medium was studied in experiments on normotensive control rats (NKWR) and spontaneously hypertensive rats (SHR). Extracellular elevation of calcium resulted in an increase in the number of vesicles, which was more demonstrable in SHR than in NKWR. After preliminary adrenalectomy the same high concentration of calcium in incubation medium did not induce any changes in the number of vesicles in both animal groups. The decrease of calcium concentration did not produce any changes in the number of vesicles in SHR or NKWR before and after adrenalectomy. The increase of the number of vesicles in response to high extracellular concentration of calcium is assumed to be a means of raising the active surface of the smooth cells and compensates for membrane deficiency seen under pathology.

Animals↗
PubMed1980

[Mesangial kidney cells: structure and function under normal and pathological conditions].

A review of the data on the structure and functions of mesangial cells (MC) and mesangial matrix of the kidneys in normal subjects under experimental conditions and in human pathology is presented. An important role of MC in purification of the glomerular filter is emphasized, their participation in regulation of the glomerular blood flow, the possibility of renin production by them and other functions are considered. Most frequent lesions of MC and their importance in the development of glomerular pathology of the kidneys are described. The nature of MC is discussed.

Cell Membrane↗
PubMed1980

[Histogenesis and diagnostic of kidney cancer in the light of electron microscopic data].

Electron microscopic examinations of human renal carcinoma showed that both light and dark (granular) differentiated tumour cells may have ultrastructural features of the cells of any nephron segment. In the light of these results and concepts of the capacity of undifferentiated tumour cells for specific differentiation, the decisive importance in histogenesis (cytogenesis) of the renal carcinoma belongs not to the site of its origin in one or another nephron segment but to the level of differentiation of stem cells (polypotent or monopotent) undergoing malignization and to the direction of their further differentiation. The paper presents concrete ultrastructural differential diagnostic features of renal carcinoma cells.

Cell Transformation, Neoplastic↗
PubMed1979

[Dynamics of renin production by the juxtaglomerular and mesangial cells of individual rat kidney glomeruli following adrenalectomy].

Adrenal incompetence developed in rats 6 weeks after adrenalectomy without any salt and hormonal compensation. In individual fragments of the isolated glomeruli containing juxtaglomerular cells (JGC) renin activity increased 1.2 times on the average, and there was revealed renin-like activity (RLA) in the fragments containing mesangial cells (MC). Signs of intensified renin secretion (expressed in reduction of granule count, marked development of granular endoplasmic reticulum, Golgi complex and microtubules) were noted in the JGC. In MC such organoids were well developed, but no granules were revealed. The following occurred in 8 to 12 weeks with the restoration of the 11-OCS and sodium level in the plasma: renin JGC activity became normal, RLA activity in MC disappeared, and the initial ultrastructure of both of these cells was restored. The reserve role of MC as the source of renin-like substances was confirmed.

Adrenal Glands↗
PubMed1979

[Correlation of wall thickness and the luminal diameter of the arterial vessels of the kidneys in hypertension].

The autopsy material was used to study the ratio of the wall thickness and the lumen diameter in arch and interlobular arteries and arterioles of the kidneys in patients with hypertension and in the control group. A statistical analysis revealed in interlobular arteries and arterioles of the age group of 30-49 years a slight but a significant shift of the parameter under study towards more severe degrees of involvement. This was confirmed by the frequency of different degrees of damage. No significant differences in changes observed in interlobular arteries and arterioles were found. This method is recommended for the study of the structural changes of intrarenal arteries.

Adult↗
PubMed1978

[Subcellular morphology of the tubules in the rat compensatory-hypertrophic kidney according to the morphometric data].

Ultrastructure of sinuous proximal and straight distal tubules, as well as collecting tubules of the cortical layer in the rat kidney fixed with perfusion has been studied with electron microscopic morphometry 7--8 weeks after contralateral nephrectomy. The volume of mitochondria, the area of their crisis, the area of the membranes in intracellular labyrinth and other morphometrical parameters have been calculated. Relative volume of mitochondria in the nephron areas studied does not change, while in the collecting tubules it is elevated. The area of crisis in mitochondria and "coefficient of morphological organization level" of these organells in the proximal tubules are increased, in the distal do not change, in the collecting tubules increase again. Subcellular changes described are discussed mainly in terms of enhancement of concentrating function of the compensatory-hypertrophic kidney.

Adaptation, Physiological↗
PubMed1978

[So-called medullary fibromas of the kidney].

This is the first description in the national literature of morphology of the so-called medullar fibromas of the human kidney which are considered to be hormonally-active (producing prostaglandines) tumours or tumour-like focal hyperplasias of interstitial cells of the kidney medullary layer.

Adult↗
PubMed1977

[Reserve production of renin by glomerular mesangial cells following experimental decrease in renal circulation].

The aorta was partially constricted between the origins of the two renal arteries in rats. The renin activity was studied separately in the capillary parts of the isolated glomeruli and in their arterioles. The renin activity was found in the capillary parts of the glomeruli 3 to 4 weeks after the constriction. The rough and smooth endoplasmic reticulum and the Golgi complex of the mesangial cells were activated at this period. The authors consider these results as a confirmation of the hypothesis on the reserve renin production by mesangial cells under prolonged decrease of renal circulation.

Animals↗
PubMed1977

[Role of injury in the appearance of "activated" smooth muscle cells].

The ultrastructure of the smooth muscle tissue was studied in the posterior vena cava in rats after the disturbance of blood outflow, in the stomach following resection of half of its fundus and cecum after constriction of its ascending limb. "Activation" of the smooth muscle was found to reflect the stage of the cell ultrastructure injury, and then the processes of intracellular regeneration. Analysis of the correlation between the DNP-synthesizing and the "activated" cells showed the latter to be of local origin, from the differentiated myocytes.

Animals↗
PubMed1976

[Ultrastructure of the duodenal mucosa in rats under stress].

Electron microscopy study of the duodenal mucosa of rats after a 24-hour restrain stress was conducted in a special apparatus. Moderate changes of enterocytes chiefly consisting of focal destruction of mitochondrial cristae and increase in the number of lysosomes were revealed. These results correlate with the previously published data on histochemical study of the same objects. The changes of the goblet cells and of the blood vessels are described.

Animals↗
PubMed1976

[Electron-microscopic radioautography of DNA-synthesizing cells of growing rat smooth muscle tissue].

DNA-synthesizing cells of rat stomach muscle tissue following 50% resection of the fundal part, identical cells of the vena cava after disturbance of the blood out flow, and of the appendix on contraction of the ascending part of the large intestine were studied by electron microscopic autoradiography. DNA synthesis in the differentiated myocyte nuclei of the stomach muscle tissue, and of the "activated" myocytes of the stomach and the vein was observed. There were signs of asynchronous DNA synthesis in the nuclei of some smooth muscle cells and fibroblasts.

Animals↗