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A review of literature reveales the current conception of Russian and foreign authors on the cellular and humoral pathogenetic mechanisms of ischemic and reperfusion injury of kidney transplant.

Comparative analysis of relationships between individual peculiarities of the structure of nephrons in intact and hydronephrotic right rabbit kidneys, on one hand, and the degree of expression of nephrotoxicity of gentamicin with respect to the only intact and as well hydronephrotic left kidney, on the other hand, was undertaken. Damage of the kidney by this antibiotic is more expressed in rabbits with smaller diameter of distal convoluted tubules of nephrons and smaller size of the cells lining their lumen. These peculiarities of the structure of nephrons lead to predisposition to the gentamicin-induced nephropathy in intact rabbits to a higher degree than in animals with hydronephrosis. The method of predicting individual predisposition to gentamicin-induced nephropathy has been patented (No. 7722 of 13.10.2005).

By light microscopy, the morphofunctional state of mesonephros was studied for various sturgeons and bony fishes taken from natural waters. Different changes were recorded in structural-functional elements of nephrons of the mesonephros. The most frequent disturbances are hemorrhages in the intertubule tissue of kidneys, hyalinosis of vessel walls, swollen epithelium, inflammations. The revealed disturbances may be regarded as a response to negative environmental impacts.

The aims of the present study were to investigate the nature of morpho-functional changes in the kidneys in mother, fetus and the offspring subjected to the dosed effect of vibration during gestation. The study was performed in pregnant female Wistar rats (n = 28), fetuses (n = 26) and the offspring aged 3 months (n = 20). Rats were subjected to vibration from Day 9 to Day 19 of gestation (the period of intensive metanephros development), using vibration test bench with fixed parameters: frequency of 32 Hz and acceleration of 50 m/s2. Renal structures were studied using morphometric methods, the ultrastructure of renal cells was examined. In pregnant females and in mature offspring, the nephrons of subcapsular, inrtacortical and juxtamedullary zones were studied. Taking into account organo- and histogenesis of embryonic kidney, in fetuses only nephrons of the last three stages of differentiation and S-shaped tubules were studied. It was found that in adult animals juxtamedullary and subcapsular renal zones were most sensitive to the effect of vibration. Morpho-functional signs of the damage to the filtration barrier were also noted. In the metanephros of fetuses, the maturation of nephrons was retarded, and the regular formation of intercellular junctions was disturbed. In the kidneys of immature offspring the number of nephrons was increased.

Aim: Elucidation of the role of saluresis and osmotic diuresis in renal function of patients with chronic renal failure., Material and Methods: The trial included 68 subjects, among them 25 patients with chronic renal failure (CRF) of the third and fourth degree aged 16 to 72 years. Enzyme immunoassay was used to measure osmolality, sodium, potassium, magnesium, calcium and creatinine concentrations in the serum and urine as well as urine prostaglandin E2., Results: Renal function was studied in CRF patients with a 75-90% fall of glomerular filtration rate. Creatinine clearance was 19.9 +/- 0.96, it varied in different patients from 10.6 to 29.7 ml/min. It is shown that diuresis does not correlate with the total ion excretion (Na+ plus K+)(r = 0.946, p < 0.0001). A correlation was found between excretion of these ions and Mg2+ ions this indicating location of reabsorption reduction in the thick ascending limb of Henle loop. In CRF patients (Na+ plus K+) excretion correlated with PGE2 excretion (r = 0.65, p < 0.0001)., Conclusion: It is suggested that at this stage of chronic renal failure the mechanism of a diuresis increase is not due to osmotic diuresis but rather to secretion of prostaglandin E2 which inhibits cation reabsorption and stimulates diuresis. Differences are considered between osmotic diuresis and different types of saluresis; their possible mechanisms are discussed.

Renal enzymuria was measured in hemophiliacs: enzymes of tubular epithelium, associated with cytomembrane, lysosomal, cytosolic, marker of glomerular defect. The enzymological markers indicated impairment of nephron tubular component in all the examinees. Patients with hematuria had also defects in glomerular apparatus. A direct relationship existed between the severity of calciuria and activity of membrane-associated enzymes of canalicular epithelium.

The pathogenetic treatment of acute renal insufficiency (ARI) of the type of "shock kidney" started early in the disease changes the clinico-anatomical picture of ARI. Therapeutically conditioned pathomorphosis of ARI may exist. According to the data of the literature and the author's data based on morphological analysis of 400 autopsy cases of ARI, the ARI pathomorphosis consists of the following : (1) emergence of reversible ARI forms (when the treatment is started early and nephron is not deeply affected); (2) disappearance of some morphological signs of ARI (reaction of the renal tissue to cyclinders, tubulorexis); (3) appearance of unusual regeneration of nephroepithelium in deep affection of the kidneys. Renal changes associated with therapy should be regarded as pathology of ARI therapy.

Morphological bases of functional potentialities of nephrons were studied in the experiment with 115 two-month rats under conditions of general momentary hyperthermia. The size of renal corpuscles tends to diminish. It is found that damages occur mainly in epithelium of the proximal parts of nephrons with disturbances in the reabsorption apparatus. The lowered epithelium reabsorptivity is directed to provide survival of the cells and their further participation in reparative processes.