The aim of this study was to assess the impact of metribuzin in surface waters on fish under experimental conditions. The effects of subchronic exposure to metribuzin on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver) and on activity of some biochemical markers (CYP450, EROD) in Danio rerio were investigated during a 28-day toxicity test. Ju...

The effects of point-source and diffuse discharges on resident populations of brown bullhead catfish (Ameiurus nebulosus (LeSueur, 1819)) in the Waikato River (New Zealand) were assessed at sites both upstream and downstream of point-source discharges. At each site, the population parameters, relative abundance, age structure, and individual indices, such as condition factor, organ (gonad, live...

Caffeic acid phenethyl ester (CAPE), a natural component of propolis, shows anticarcinogenic properties in the modified resistant hepatocyte model when administered before initiation or promotion of hepatocarcinogenesis process; however, information about the mechanism underlying this chemoprotection is limited. The aim of this work was to characterize the effect of CAPE on cytochrome P450 (CYP...

Cytochromes P450 (CYP) belong to the most important biotransformation enzymes, therefore, their inhibition may lead to serious pharmacological and toxicological consequences. Albendazole (ABZ) is a benzimidazole anthelmintic widely used in human and veterinary medicine. The effects of ABZ on CYP were investigated on the rat (Rattus norvergicus) and mouflon (Ovis musimon) hepatic microsomes. Bes...

Extracts from semi-permeable membrane devices (SPMDs) deployed on beaches in Prince William Sound (PWS), Alaska, were used to evaluate if complex contaminant mixtures from different sources can be distinguished by the resulting cytochrome P450 1A (CYP1A) activity in exposed test animals. Deployment sites included canneries, salmon hatcheries, and beaches where lingering oil remains from dischar...

Biochemical and histochemical studies were conducted in aflatoxin B1-induced liver tumors in adult rainbow trout. Specific activities of the phase I enzymes, ethoxyresorufin-O-deethylase (EROD), microsomal and cytosolic epoxide hydrolase (mEH and cEH), aldehyde dehydrogenase (ALDH) and DT-diaphorase, and the phase II enzymes, gamma-glutamyltransferase (gamma-GT), glutathione transferase (GST) a...

Sexually mature pigs are known to possess high concentrations of testicular steroids, which have been shown to change the activities of cytochrome P450 in vitro. The aim of the present study was to evaluate the regulation of CYP1A and CYP2E1 activity by the steroids dihydrotestosterone (DHT), 3β-androstenol, 17β-estradiol and 17α-estradiol. Catalytic activities of 7-ethoxyresorufin O-deethylase...

The present investigation was carried out to study the expression of major cytochrome P450 (CYP) isozymes in streptozotocin-induced diabetes with concomitant insulin therapy. Male Sprague-Dawley rats were randomly assigned to untreated control, streptozotocin-induced diabetic, insulin-treated groups and monitored for 4 weeks. Uncontrolled hyperglycemia in the early phase of diabetes resulted in...

Coelenterazine (3,7-dihydro-2-(p-hydroxybenzyl)-6-(p-hydroxyphenyl)-8-benzylimidazolo[1,2-a]pyrazin-3- one) is a substrate for the bioluminescence reaction in many marine animals. Recent work showed that CLZn, its synthetic analogue CLZm, and their common oxidation product coelenteramine (CLM) have strong antioxidative properties in acellular lipid peroxidation systems as well as in rat hepatoc...

A growing body of evidence suggests that polychlorinated naphthalenes (PCNs) may be fairly widespread environmental contaminants. This may be cause for concern because exposure to PCNs has been linked to dioxin-like biological responses in a wide variety of species. This study used three in vitro bioassays to characterize the dioxin-like potency of 18 individual PCN congeners and 1 PCN metaboli...