Cadmium (Cd), an environmental and industrial pollutant, poses a potential threat and affects many systems in human and animals. Although several reports on Cd toxicity were presented, the acute effect of Cd on systemic and thrombotic events was not reported so far. Cd (2.284 mg/kg) or saline (control) was injected intraperitoneally (ip), and the systemic parameters were assessed in mice. Compared to control group, acute intraperitoneal injection of Cd, in mice showed significant quickening of platelet aggregation (P<0.001) leading to pial cerebral thrombosis. Likewise, Cd exposure caused a significant increase in white blood cell numbers (P<0.05) indicating the occurrence of systemic inflammation. Also, alanine aminotransferase (ALT) (P<0.05) and creatinine (P<0.01) levels were both significantly increased. Interestingly, the superoxide dismutase activity was significantly decreased in Cd treated group compared to control group (P<0.001), suggesting the occurrence of oxidative stress. We conclude that the Cd exposure in mice causes acute thromboembolic events, oxidative stress and alter liver and kidney functions., M.A. Fahim ... [et al.]., and Obsahuje seznam literatury
Sexually mature female Wistar rats were given daily intragastric doses of ethinylestradiol (EE) and levonorgestrel (LE) used normally in women: (1) 0.03 mg EE and 0.05 mg LE; (2) 0.04 mg EE and 0.075 mg LE; (3) 0.03 mg EE and 0.125 mg LE. All groups were treated for 6 months in 5-day cycles (four-day treatment with a one-day break),
i.e. for 36 sexual cycles. In rat kidneys, the activity of succinic dehydrogenase, NADPH-tetrazolium reductase, Mg2 + -ATPase and alkaline phosphatase were decreased, while those of lactate dehydrogenase, acid phosphatase and glucose-6-phosphatase were enhanced. We have found a correlation between enzymatic changes and ultrastructural changes in epithelial renal cells. These changes may reflect: (1) inhibited oxidative processes associated with the mitochondrial and microsomal systems of electron transport; (2) a compensatory increase in anaerobic processes; (3) increased glyconeogenesis; (4) inhibited transport processes and increased cellular catabolism. The kidney cortex and medulla did not show any significant morphological changes after 6 months of treatment. The study has shown that EE/LE combinations produce histochemical and ultrastructural changes in the kidney, which are dependent on the doses of gestagens.
For better understanding of pathophysiological processes leading to increased retention of sodium as a consequence of hyperlipidemia, the properties of renal Na,K-ATPase, a key enzyme involved in maintaining sodium homeostasis in the organism, were studied. Enzyme kinetics of renal Na,K-ATPase were used for characterization of ATP- and Na+-binding sites after administration of fish oil (FO) (30 mg · day-1) or atorvastatin (0.5 mg·100 g-1 day-1) to healthy Wistar rats and rats with hereditary hypertriglyceridemia of both genders. Untreated healthy Wistar and also hypertriglyceridemic female rats revealed higher Na,K-ATPase activity as compared to respective untreated male groups. Hypertriglyceridemia itself was accompanied with higher Na,K-ATPase activity in both genders. Fish oil improved the enzyme affinity to ATP and Na+, as indicated by lowered values of K m and K Na in Wistar female rats. In Wistar male rats FO deteriorated the enzyme in the vicinity of the Na+-binding site as revealed from the increased K Na value. In hypertriglyceridemic rats FO induced a significant effect only in females in the vicinity of the sodium binding sites resulting in improved affinity as documented by the lower value of KNa. Atorvastatin aggravated the properties of Na,K-ATPase in both genders of Wistar rats. In hypertriglyceridemic rats protection of Na,K-ATPase was observed, but this effect was bound to females only. Both treatments protected renal Na,K-ATPase in a gender specific mode, resulting probably in improved extrusion of excessive intracellular sodium out of the cell affecting thus the retention of sodium in hHTG females only., N. Vrbjar ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The inhibitory effect of 2 % ethanol (400 mM) in the incubation medium on several characteristics of the Na+-ATPase of basolatcral plasma membranes from rat kidney proximal tubular cells was investigated. Ethanol did not change the Km of the enzyme for Mg2+, ATP or Na + ; it did not change either the optimal pH or temperature values of the incubation medium for the enzyme to act and finally, it did not affect the apparent energy of activation of the enzyme. It was also found that 2 % ethanol produced stronger inhibition of the ATPase when it is in an activated or stimulated state, than when it is working at its lower basal level. The presented results can be explained by assuming that 2 % ethanol in the incubation medium inhibits Na +-ATPase activity by affecting the enzyme structure as well as its activating mechanism.
The extent of ADP.Fe/NADPH-induced lipid peroxidation measured as production of thiobarbituric acid-reactive substances (TBARS) was determined in isolated membranes from cerebral cortex, heart and kidney of 21-days- old rats. The time course of lipid peroxidation showed higher production of TBARS in cerebral cortex than in heart and kidney. Our data indicate that high level of TBARS production is not due to high activity of NADPH oxidoreductase but due to high content of endogenous lipids in cerebral cortex membranes that could be modified. Higher production of TBARS in cerebral cortex is the result of higher content of lipids in cerebral cortex membranes because NADPH cytochrome c reductase activity in membranes of cerebral cortex is lower than that of heart and kidney.
An unidentified myxosporean parasite (CKX) is described from the kidney of approximately 80% of spawning coho salmon Oncorhynchus kisutch (Walbaum) in British Columbia, Canada and Washington, United States of America. Morphological features were described using light and electron microscopy. Sequencing of polymerase chain reaction (PCR) amplified 18S ribosomal RNA gene and in situ hybridisation were used to further characterise CKX. The parasite occurred with a focal distribution within tubule epithelial cells, the tubule lumen and the interstitium as primary cells containing from one to at least 16 secondary cells. Luminal stages were degenerate and sporogony was not observed. In situ hybridisation using a digoxygenin-labelled DNA probe confirmed CKX to be the source of DNA used in PCR analyses. CKX 18S rDNA sequences were most similar (97%) to those of Sphaerospora oncorhynchi. Phylogenetic analysis revealed similarities among the 18S rDNA sequences of CKX, S. oncorhynchi and Myxidium lieberkuehni. CKX is hypothesised to be the abortive extrasporogonic development of a Sphaerospora sp. or Myxidium sp. occurring in immune-incompetent spawning and senescent salmon.