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Farmaka ve vodním prostředí a jejich vliv na ryby
BURKINA, Viktoriia
In this thesis, the impact of atenolol, verapamil, dexamethasone, clotrimazole, and PBSA on the physiological condition and health of rainbow trout (Oncorhynchus mykiss) were studied in vivo and in vitro. The sub-chronic test of atenolol, including at the environmentally relevant concentration, demonstrated that only the fish exposed to atenolol at a concentration of 1000 ?g?L-1 may be at a higher risk of oxidative stress. The second pharmaceutical compound studied was an L-type calcium channel blocker, verapamil. Despite the relatively high concentration of verapamil included in the experiments, the rates of seven hepatic CYP450-mediated reactions (EROD, MROD, PROD, BFCOD, COH, and PNPH) were unchanged in the exposed rainbow trout. This indicates that the activities of the selected CYP450 enzymes were not affected. Exposure to the highest concentration of PBSA (1000 ?g?L-1) led to significantly inhibited glutathione reductase activity. The activities of the EROD, MROD, and PROD enzymes gradually increased, beginning at the environmentally relevant concentrations. We suggest that long-term exposure to PBSA could cause oxidative stress in fish, as indicated by the decreased activity of GR. Moreover, PBSA could interact with intracellular receptors due to the elevated activities of CYP1A (EROD and MROD) and CYP2B (PROD). Rainbow trout showed multiple responses after exposure to clotrimazole. Changes in the haematological parameters in the exposed rainbow trout suggested that the immune system and haemoglobin synthesis were affected. The antioxidant defence enzymes that responded to the clotrimazole exposure influenced the oxidative stress status of the fish. Sub-chronic exposure to clotrimazole did not lead to oxidative stress in any of the fish tissues studied, as indicated by the unchanged TBARS levels. Hepatic energetic pathways were activated in the tested groups after 42 days of exposure to clotrimazole. High levels of glutathione S-transferase were seen in the liver and gill tissues, possibly associated with the detoxification of clotrimazole. The interaction of clotrimazole with intracellular receptors can be expected due to the changes in the catalytic activities of CYP1A1 and CYP3A. The BCF levels in the muscle tissue suggest a moderate bioaccumulation of CLO. The relatively long elimination period for CLO in the fish kidney (half-life = 29 days) may imply a greater potential for adverse effects in this organ. This finding is significant in view of the structural disturbances that appeared in the kidney and testis. The changes observed in the kidney were most prominent in the tubular epithelial cells. Changes in the gonads were only visible in the male specimens, and the pathological changes in the testis may indicate a disruption of steroidogenesis. The potential of clotrimazole and dexamethasone to inhibit CYP450 enzyme activity in rainbow trout hepatic microsomes was investigated in vitro. Clotrimazole non-competitively inhibited EROD activity in the hepatic microsomes, while BFCOD activity was competitively inhibited. PNPH activity was only slightly reduced in the presence of clotrimazole, indicating that it does not significantly interact with CYP2E1. The presence of dexamethasone in the incubations did not affect any of the CYP450 enzymes investigated. Everything considered, the results of the study confirmed that the presence of clotrimazole in the environment is of concern with respect to its impact on the health status of fish. In this thesis, the data of the actual effects of several PPCPs on fish were discussed. Based on the response of selected molecular endpoints, the cardiovascular and anti-inflammatory drugs studied do not present a significant risk for fish, while the antifungal drug and UV-screening agent that were tested may disrupt several physiological processes in fish.
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Antropogenní tlaky na stav půd‚ vodní zdroje a vodní ekosystémy v české části mezinárodního povodí Labe: Výzkum vlivu polutantů přítomných ve vodním prostředí na ryby
Český hydrometeorologický ústav, Praha ; Umea University, Sweden ; Výzkumný ústav rybářský a hydrobiologický ve Vodňanech, Vodňany ; Jihočeská univerzita v Českých Budějovicích, České Budějovice ; Stará, Alžběta ; Steinbach, Christoph ; Grabicová, Kateřina ; Burkina, Viktoriia ; Golovko, Oksana ; Turek, Jan ; Sudová, Eliška ; Máchová, Jana ; Valentová, Olga ; Velíšek, Josef ; Kroupová, Hana ; Kolářová, Jitka ; Fedorova, Ganna ; Žlábek, Vladimír ; Grabic, Roman ; Li, Zhihua ; Randák, Tomáš
Projekt se zabývá vlivem běžných komunálních zdrojů znečištění na vodní prostředí. Získal data charakterizující kontaminci vodních ekosystémů vybranými biologicky aktivními látkami nad a pod vytipovanými zdroji komunálního znečištění a hodnotil jejich vliv na indikátorové organismy - ryby. Je uvedeno vyhodnocení souvislostí mezi výskytem vybraných polutantů ve vodním prostředí a biologickými změnami u indikátorů organismů v laboratorních i přírodních podmínkách.
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