Effect of morphine and naloxone on oxidative metabolism during experimental renal ischemia and reperfusion.

During experimental renal ischemia and reperfusion in rabbits, morphine as well as naloxone significantly inhibited the increased superoxide anion (O2-) generation by resting and opsonized zymosan-stimulated phagocytes in renal venous blood. Morphine with naloxone in combination inhibited O2- generation to a lesser extent than that observed when these drugs were used separately. Morphine and/or naloxone did not significantly affect erythrocyte superoxide dismutase (SOD-1), glutathione peroxidase (GPx) and catalase activities or malonyldialdehyde (MDA) concentrations in venous blood during renal ischemia. During reperfusion there was a tendency to a slight reduction of erythrocyte catalase activity in morphine-treated animals, and to slight diminutions of erythrocyte SOD-1 and GPx activities and erythrocyte MDA concentrations in rabbits treated with naloxone and morphine in combination. These results indicate that opioid receptor agonists and antagonists modify the response of the kidney to acute injury. These effects may have relevance to the pattern of oxidative stress seen in patients with acute ischemic renal failure.

[Some indices of peripheral blood oxidative metabolism during acetate and bicarbonate hemodialysis in patients with chronic uremia]. / Niektóre wskazniki metabolizmu tlenowego krwi obwodowej podczas hemodializy octanowej i wodoroweglanowej u chorych z przewlekla mocznica.

Whole blood superoxide anion generation, erythrocyte superoxide dismutase (SOD-1) and catalase activities and erythrocyte and plasma malonyldialdehyde concentrations were evaluated during cuprophane hemodialysis using bicarbonate and acetate dialysate. Superoxide anion generation by resting phagocytes was found to be significantly higher during bicarbonate hemodialysis, while its generation by opsonized zymosan--stimulated phagocytes did not differ between hemodialyses with both kinds of dialysates. Changes in the erythrocytes SOD-1 activities, found in the initial period of hemodialysis, were independent of the kind of dialysate, while erythrocyte catalase activity was higher during acetate hemodialysis in comparison with bicarbonate one. The kind of dialysate did not affect extent of erythrocyte membrane lipid peroxidation, while plasma lipid peroxidation was lower during acetate hemodialysis in comparison with bicarbonate one. In vitro studies with blood cells incubated with acetate or bicarbonate ions in concentrations, which are observed in vivo during hemodialysis, suggest that probably these ions do not directly affect superoxide anions generation, erythrocyte SOD-1 and catalase activities and erythrocyte membrane lipid peroxidation.

[Generation of active oxygen compounds by whole blood granulocytes in patients with chronic renal failure]. / Generacja aktywnych zwiazków tlenowych przez granulocyty krwi pelnej u chorych z przewlekla niewydolnoscia nerek.

In patients with chronic renal failure (crf) on conservative treatment whole blood granulocyte superoxide anion (O2-) generation was significantly decreased. Regular hemodialysis treatment did not induce its significant improvement. As granulocyte O2- generation determines production of other active oxygen compounds, this phenomenon may lead to the impairment of phagocyte bactericidal activity and increased susceptibility to infections in crf. Various methods of determination of active oxygen compounds give incomparable results.

Whole blood superoxide anion generation and efficiency of some erythrocyte antioxidant systems during recombinant human erythropoietin therapy of uremic anemia.

Six chronic uremic patients on regular hemodialysis treatment were given recombinant human erythropoietin (r-huEPO) in a dose of 50 U/kg of body weight intravenously thrice weekly for 14 weeks. Following r-huEPO therapy, unstimulated whole blood superoxide anion (O2) generation did not change significantly, while opsonized zymosan-stimulated whole blood O2 generation increased. At the same time, erythrocyte superoxide dismutase and, in particular, glutathione peroxidase activities were found to be reducing with concomitant lowering of erythrocyte malonyldialdehyde (MDA) concentrations and increase in plasma MDA concentrations.

Free oxygen species metabolism during haemodialysis with different membranes.

In 10 chronic uraemic patients free oxygen species metabolism was evaluated during the early period of haemodialysis with cuprophane, polyacrylonitrile and polysulphone membranes. Cuprophane haemodialysis was found to induce an increased generation of superoxide anion by both unstimulated and opsonised-zymosan-stimulated peripheral blood phagocytes, which was accompanied by a significant depression of erythrocyte superoxide dismutase activity and augmented erythrocyte membrane lipid peroxidation. Haemodialysis with polyacrylonitrile membrane did not induce significant changes in superoxide anion generation, erythrocyte superoxide dismutase activity, and erythrocyte and plasma malonyldialdehyde concentrations. The same was found with polysulphone membrane, except for plasma malonyldialdehyde, the concentration of which was significantly decreased. Our results suggest that use of polyacrylonitrile or polysulphone membranes for haemodialysis seems to be beneficial with regard to free oxygen radical metabolism.

Superoxide anion generation and lipid peroxidation processes during hemodialysis with reused cuprophan dialyzers.

In 11 chronic uremic patients superoxide anion (O2-.) generation and lipid peroxidation processes were determined during hemodialyses with cuprophan dialyzers used three times. Intradialytic changes observed during the first 20 min of hemodialysis, that is the period of the most marked alterations, with consecutive uses of the same dialyzer included: decreased whole blood O2-. generation at rest and following stimulation with opsonized zymosan, decreased reductions in the erythrocyte superoxide dismutase (SOD-1) activity, increased reductions in the plasma malonyldialdehyde (MDA) concentrations, and unchanged erythrocyte MDA concentrations. However, immediately before hemodialysis with third-used dialyzer whole blood O2-. generation at rest and following opsonized-zymosan stimulation, and erythrocyte SOD-1 activity were slightly, but statistically significantly, lower (p less than 0.05), while plasma MDA concentrations were higher (p less than 0.05) than those before hemodialysis with first-used dialyzer; erythrocyte MDA concentrations remained unchanged. The results seem to indicate that dialyzer reuse may exert beneficial effects on whole blood O2-. generation and protect erythrocyte membrane lipids from peroxidation, but, however, it leads to slightly increasing predialysis plasma lipid peroxidation.

Hemodialysis and the acute-phase response in chronic uremic patients.

In comparison with healthy persons, chronic uremic patients on regular hemodialysis treatment had significantly higher blood serum concentrations of alpha 1-acid glycoprotein, ceruloplasmin and C4 complement component, while levels of haptoglobin, C3 and transferrin were lower. Serum alpha 2-macroglobulin and alpha 1-antitrypsin levels were similar in both groups. Hemodialysis with cuprophan membrane induced only slight changes in some of these glycoproteins during a 48-hour follow-up period. Seven hours after termination of hemodialysis slight, but significant, decreases in blood serum transferrin and alpha 1-antitrypsin concentrations were observed. Hemodialysis thus does not seem to induce a conspicuous acute-phase reaction.

Effect of hemodialysis on T lymphocyte subsets, con-A-activated suppressor cell activity, and interleukin-2 receptor expression on lymphocytes in chronic uremic patients.

Effect of hemodialysis (HD) on some indices of immune response was studied in nine chronic uremics. Total lymphocyte, OKT4+, and OKT8+ cell numbers significantly decreased during the first 20 min of HD, and they were decreased till the third hour of the procedure, whereas the OKT4+/OKT8+ cell number ratio did not change significantly. Before HD, Con-A--activated suppressor cells exerted a stimulatory action on autologous responder cells measured in two-step culture. During HD, Con-A-activated suppressor cell activity transiently appeared, with its peak at 60 min after the start of HD. It was accompanied by a transient rise in lymphocyte count with spontaneous interleukin-2 (IL-2) receptor expression, whereas the number of cells expressing IL-2 receptor following phytohemaglutinin (PHA) stimulation was progressively decreased during HD. A significant correlation was found between the increment of Con-A-activated suppressor cell activity and the increment of spontaneous IL-2 receptor expression on lymphocytes during one single blood flow through the dialyzer. The results supply further evidence that HD may impose additional disturbances on immune regulation in chronic uremics.

[Effect of hemoperfusion on plasma oxidizing capacity and erythrocyte sensitivity to oxidation in patients with chronic uremia]. / Wplyw hemoperfuzji na wlasciwosci utleniajace osocza i wrazliwosc krwinek czerwonych na utlenianie u chorych na przewlekla mocznice.

An effect of haemoperfusion on plasma oxidizing capacity and erythrocyte sensitivity to oxidation was investigated in patients with the chronic uremia. It was found that plasma oxidizing capacity measured with NTB reduction is more pronounced in patients with the chronic uremia than in normal subjects. Oxidizing capacity of plasma is increased at the beginning of haemoperfusion. This effect is clearly seen during single pass of blood through the column with activated carbon. Erythrocyte sensitivity to oxidation following their suspension in the normal saline with phosphate buffer and measured with ascorbic-cyanate test does not differ significantly in patients with the chronic uremia and healthy subjects and does not change markedly during haemoperfusion.

Superoxide anion generation, erythrocytes superoxide dismutase activity, and lipid peroxidation during hemoperfusion and hemodialysis in chronic uremic patients.

In 11 chronic uremic patients superoxide anion generation in whole blood, both without and with opsonized zymosan stimulation, was lower than that in 11 healthy controls, while erythrocyte superoxide dismutase (SOD-1) activity and erythrocyte and plasma malonyldialdehyde (MDA) concentrations were elevated. During hemoperfusion (HP) and hemodialysis (HD) superoxide anion generation transiently significantly increased. Changes in the erythrocyte SOD-1 activity and plasma and erythrocyte MDA concentrations during HP suggested that this procedure exerted beneficial effects on lipid peroxidation. On the other hand, during HD erythrocyte membrane lipid peroxidation seemed to be enhanced even further; this phenomenon took place mainly within the dialyzer and a decrease in the erythrocyte SOD-1 activity seemed to be one of the contributing factors. Results of in vitro experiments with cross-incubation of erythrocytes and blood plasma and incubation of whole blood with cuprophan membrane suggest existence of an SOD-1 activator in the uremic blood plasma, which is possibly eliminated during HD.

Effect of verapamil on chemiluminescence of peripheral blood neutrophils during hemodialysis in chronic uremic patients.

Luminol-dependent chemiluminescence of resting and opsonized zymosan-activated neutrophils isolated from the peripheral blood was determined in 10 chronic uremic patients during early period of hemodialysis without verapamil or preceded by verapamil injection. Verapamil was found to diminish depression of neutrophil chemiluminescence both at rest and following activation with opsonized zymosan. The drug also diminished transient hemodialysis neutropenia. The results seem to indicate that verapamil may exert beneficial effects on inflammatory reactions induced by hemodialysis in chronic uremics.

Ultrastructural markers of renal tubular transport in rats under physiological conditions.

Mitochondria of the proximal and distal tubules which are in different configurational states of epithelial cells and their surface--volume relationship of intercellular spaces and basal infolded channels were evaluated in rats. The evaluation was performed with stereological methods. The studies were carried out on 5 rats under physiological conditions using electron microscopy. Mitochondria within the proximal and distal tubules were found to occur in transitional states close to the orthodox state. However, mitochondria within the proximal tubules were in a higher energy state, closer to the orthodox state when compared with those within the distal tubules. Surface--volume parameters of intercellular spaces and basal infolded channels were unexpectedly higher than the relation to active ion transport as well as indiscernible permeability of the distal tubular basement membrane.

Ultrastructural markers of tubular transport within the rat nephron in experimental diabetes insipidus.

Using stereological methods mitochondrial energy states and intercellular spaces with basal infolded channels were evaluated in proximal and distal tubules in rats. The studies were performed on animals with experimental diabetes insipidus and on control rats by means of electron microscopy. No significant differences were found in mitochondrial energy states and sizes of intercellular spaces with basal infolded channels in the proximal tubules, which indicates undisturbed transport in this nephron segment. However, significant differences of these parameters were found in the distal tubules. In diabetes insipidus mitochondrial energy states approximated the condensed state, while in the control animals they were similar to the orthodox state. Intercellular spaces became significantly narrowed in diabetes insipidus in comparison with these in the controls. These observations suggest that mitochondrial energy states may be considered as ultrastructural markers of active tubular transport, while intercellular spaces with basal infolded channels may reflect ultrastructural counterparts of water transport.

Degranulation of peripheral blood neutrophils during haemoperfusion in chronic uraemics.

In 10 chronic uraemics activities of some lysosomal enzymes were determined in peripheral blood neutrophils and plasma during haemoperfusion with charcoal cartridge Adsorba 300 C (Gambro). Blood plasma activities of arylsulfatases, beta-N-acetylglucosaminidase and beta-glucuronidase did not significantly change during haemoperfusion, while lysozyme activity was significantly increasing. Neutrophil contents of these enzymes decreased. The determinations of these enzyme activities revealed a positive outlet-inlet difference in blood plasma and a negative outlet-inlet difference in neutrophils during the first 20 minutes of the procedure. The results suggest that during haemoperfusion degranulation of the peripheral blood neutrophils occurs.

Ultrastructural markers of tubular transport in experimental diabetes insipidus.

Stereological analysis of changes in tubular transport markers in diabetes insipidus has been undertaken. Intracellular spaces and basal infolded channels were considered as the markers of water transport, while mitochondrial metabolic steady states were considered as the active transport markers. Transmission electron microscopic observations revealed morphometric differences in the surface area and volume of intercellular space and basal infolded channels in the distal tubules. Stereological markers of mitochondrial metabolic states demonstrated significant differences in the distal tubules between diabetes insipidus and control groups. In diabetes insipidus the volume and surface area of intercellular spaces and basal infolded channels in the distal tubules were decreased and the mitochondrial energy state was lowered.

Release of neutrophil granule factors during early period of hemodialysis: a possible cause of hemodialysis neutropenia.

In the early phase of hemodialysis progressive decreases in some enzyme activities in the leukocyte homogenate, neutrophil granule fraction and postgranular supernatant were found with concomitant rise in plasma beta-glucuronidase activity, which is indicative of the release of neutrophil granule factors into the extracellular environment. Intravenous infusion of human neutrophil granule products to rabbits induced profound transient neutropenia. The results suggest that the release of neutrophil granule factors in the early period of hemodialysis may be a possible cause of hemodialysis neutropenia.