[The effect of single and repeated administration of penicillin on the structure of the endoplasmic network of the epithelial cells in the proximal tubules of rat nephrons].

In the endoplasmic reticulum (ER) of the rat proximal tubule nephron epithelial cells three morphologically different components can be distinguished: 1) tubes and cisternae distributed relatively diffusely in the cytoplasm; 2) cisternae of paramembranous ER located along the lateral boundaries of the cell (components 1 and 2 might be either smooth or granular); 3) constantly smooth ER consisting of narrow tubules accumulated in the shape of skeins or islets. The latter are closely adjacent to the basolateral plasmalemma. Single intraperitoneal injection of penicillin, as well as its nine times repeated injections in the same dosage (over the period of 3 days at equal intervals) resulted in ultrastructural changes of the cellular ER.

[An analysis of the ultrastructure of epithelial cells of the rat proximal tubule at early stages of penicillin elimination].

A study was made of the ultrastructure of epithelial cells of the rat proximal tubules nephrons 25-30 seconds, and 15 and 30 minutes following penicillin injection. The morphological changes in the transporting cells that were observed involved the dilation of the inner cavities of canals and cisterns of the endoplasmic reticulum. The number of elements of the smooth endoplasmic reticulum concentrated on the periphery of the cell, near the basolateral border, was seen to increase.

[Morphofunctional correlates of the nephrotoxic action of cis-platin].

A single injection of 5 mg/kg cisplatin causes (in 2 days) focal changes in rat renal parenchyma. These changes correlate well with the decrease in glomerular filtration rate, increase in blood urea concentration, decrease in water load excretion. Cellular dystrophy was found in the convoluted and straight proximal renal tubules, in line with a marked thickening of basal membrane in damaged cells, that appears to account for the impairment of paraaminohippurate secretion, the increase of kidney mass and its swelling.

[Ultrastructure of proximal tubular cells of the rat nephron in the period of intense glucose reabsorption].

It has been demonstrated in rat experiment that maximal glucose reabsorption is accompanied by the increased electron density of mitochondrial matrix and the enlargement of the size of microbodies. No vacuoles have been recorded, which is at variance with the concept of the pinocytosis involvement into glucose reabsorption.

[Ultrastructure of rat proximal renal tubular epithelium during substrate stimulation of cardiotrast secretion].

An electron microscope study was made of the epithelium of rat kidney proximal tubule, following a 3 day (three times a day) injection of cardiotrast in dose of 500 mg/kg, aimed to detect some morphological equivalents of the substrate stimulation of kidney tubular secretion of organic substances. Changes have been revealed in the ultrastructure of endoplasmic reticulum, ribosomal apparatus, and microbodies.