Development of Endoplasmic Reticulum Stress during Experimental Oxalate Nephrolithiasis.

Morphological and ultrastructural study of the kidney was performed in rats with oxalate nephrolithiasis. Specific features of endoplasmic reticulum stress were evaluated during nephrolithiasis and treatment with α-tocopherol. We observed the signs of endoplasmic reticulum stress with activation of proapoptotic pathways and injury to the cell lining in nephron tubules and collecting ducts. Ultrastructural changes were found in the organelles, nuclei, and cell membranes of epitheliocytes. A relationship was revealed between endoplasmic reticulum stress and oxidative damage, which developed at the early state of lithogenesis.

[Effects of water drinking regimens on crystallization intensity in experimental nephrolithiasis].

We studied effects of water regimens on crystallization efficacy in experimental nephrolithiasis on 3 groups of Wistar male rats with initial experimental nephrolithiasis (ethylene glycol model). The animals were on free, limited and supernormal liquid intake regimen. For 3 weeks each 3-4 days we estimated 24-h diuresis, urine concentration of calcium, phosphate and oxalate ions. After 3 weeks we made a morphological examination of the kidneys. We found that limited drinking leads to an increase in urinary concentrations of oxalate- and phosphate ions which stimulate enhanced formation of calcium-containing concrements. More water intake considerably reduces oxalate and phosphate concentrations in the urine resulting in reduction of the number and size of calcium deposits in renal tissue. Thus, low liquid intake leads to intensification of urine oversaturation causing formation of renal concrements. Much liquid intake weakens oversaturation and reduces the number and size of calcium deposits in the kidneys.

[Determination of the activity of Willebrand's factor by laser analyzer of platelet aggregation]. / Opredelenie aktivnosti faktora Villebranda pri pomoshchi lazernogo analizatora agregatsii trombotsitov.

A modification of von Willebrand' factor/ristocetin cofactor activity test is proposed. Agglutination of formalin-treated platelets is monitored in the aggregation analyzer from changes in the light transmission in the specimen. The test is sensitive and reproducible. It is intended for clinical laboratories to be used in patients with hematological diseases and the endotheliopathy syndrome of different etiology.