title: Enzymatic alterations and RNA/DNA ratio in intestine of rainbow trout, Oncorhynchus mykiss, induced by chronic exposure to carbamazepine.
abstract: We investigated the effect of long-term exposure to carbamazepine (CBZ) on the enzymatic alterations and RNA/DNA ratio in intestine tissue of rainbow trout. Fish were exposed to sublethal concentrations of CBZ (1.0 microg/l, 0.2 or 2.0 mg/l) for 42 days. Digestive enzymes (proteolytic enzymes and amylase) and energy metabolic enzyme (Na(+)-K(+)-ATPase) and antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx], and glutathione reductase [GR]) in fish intestine were measured. In addition, intestinal RNA/DNA ratio was determined after 42 days exposure. Carbamazepine exposure at 2.0 mg/l led to significantly inhibited (P < 0.05) activity of Na(+)-K(+)-ATPase. Activities of the antioxidant enzymes SOD, CAT, and GPx in CBZ-treated groups gradually increased at lower concentration of CBZ (1.0 microg/l and 0.2 mg/l), then significantly inhibited (P < 0.05) at 2.0 mg/l. After 42 days, the RNA/DNA ratio in fish intestine was significantly lower (P < 0.05) in groups exposed to CBZ at 2.0 mg/l than in other groups. However, there was no statistical significance (P > 0.05) in the activities of digestive enzymes (proteolytic enzyme and amylase) and GR in all groups. In short, prolonged exposure to CBZ resulted in different responses of various enzymes and significantly lower RNA/DNA ratio in fish intestine. Furthermore, molecular and genetic mechanisms of these physiological responses in fish are not clear, which need to be further studied.
authors.affiliation: Faculty of Fisheries and Protection of Waters Research, Institute of Fish Culture and Hydrobiology, University of South Bohemia in Ceske Budejovice, Zatisi 728/II, 389 25 Vodnany, Ceske Budejovice, Czech Republic. zhihuali06@yahoo.com
authors.forename: Zhi-Hua
authors.initials: ZH
authors.lastname: Li
authors.forename: Vladimir
authors.initials: V
authors.lastname: Zlabek
authors.forename: Roman
authors.initials: R
authors.lastname: Grabic
authors.forename: Josef
authors.initials: J
authors.lastname: Velisek
authors.forename: Jana
authors.initials: J
authors.lastname: Machova
authors.forename: Tomas
authors.initials: T
authors.lastname: Randak
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002220:Carbamazepine / Q000008:administration & dosage / Q000633:toxicity*; D004247:DNA / Q000187:drug effects* / Q000378:metabolism; D004064:Digestive System / Q000187:drug effects / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D005260:Female; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects / Q000201:enzymology; D008297:Male; D017686:Oncorhynchus mykiss; D012313:RNA / Q000187:drug effects* / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors / Q000378:metabolism; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000008:administration & dosage / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D014874:Water Pollutants, Chemical; D002220:Carbamazepine; D012313:RNA; D004247:DNA; D000254:Sodium-Potassium-Exchanging ATPase