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Publications (3)3.24 Total impact

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    ABSTRACT: This work investigated the effects of copper as preventive treatment against mercury-induced alterations in young rats. Wistar rats were treated (subcutaneous) with saline or CuCl(2) · 2H(2) O (6.9 mg/kg/day) from 3 to 7 days old and with saline or HgCl(2) (5.0 mg/kg/day) from 8 to 12 days old. Rats were sacrificed 24 h after the last dose. Mercury-exposed rats presented inhibition of liver (43%) and kidney (52%) porphobilinogen (PBG)-synthase activity and serum lactic dehydrogenase activity (50%). Also, an increase of the serum creatinine and urea levels around threefold and fivefold was observed, respectively. Pre-exposure to copper partially prevented the mercury effect on liver but not on kidney PBG synthase, and prevented the increase of the creatinine levels. Blood and brain PBG synthase and serum alanineaminotransferase activities, as well as glycemia, and liver glycogen content were not altered by treatments. These results show that copper, although being an essential metal, is inefficient as a preventive agent against mercury poisoning in parameters investigated after the end of mercury exposure. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:354-359, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21429.
    Journal of Biochemical and Molecular Toxicology 07/2012; 26(9):354-9. · 1.60 Impact Factor
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    ABSTRACT: This work investigated the in vivo and in vitro effects of HgCl2 and ZnCl2 on metabolic enzymes from tissues of young rats to verify whether the physiological and biochemical alterations induced by mercury and prevented by zinc are related to hepatic and renal glucose metabolism. Wistar rats received (subcutaneous) saline or ZnCl2 (27 mg/kg/day) from 3 to 7 days old and saline or HgCl2 (5.0 mg/kg/day) from 8 to 12 days old. Mercury exposure increased the hepatic alanine aminotransferase (∼6-fold) and glucose 6-phosphatase (75%) activity; zinc pre-exposure prevented totally and partially these mercury alterations respectively. In vitro, HgCl2 inhibited the serum (22%, 10 μM) and liver (54%, 100 μM) alanine aminotransferase, serum (53%) and liver (64%) lactate dehydrogenase (10 μM), and liver (53%) and kidney (41%) glucose 6-phosphatase (100 μM) from 10- to 13-day-old rats. The results show that mercury induces distinct alterations in these enzymes when tested in vivo or in vitro as well as when different sources were used. The increase of both hepatic alanine aminotransferase and glucose 6-phosphatase activity suggests that the mercury-exposed rats have increased gluconeogenic activity in the liver. Zinc prevents the in vivo effects on metabolic changes induced by mercury.
    Cell Biology International 03/2012; 36(6):561-6. · 1.64 Impact Factor
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    ABSTRACT: This research investigated the in vivo (ZnCl2 27 mg/kg; CuSO4 10.2 mg/kg) and in vitro effects of zinc and copper on acetylcholinesterase activity of different cerebral areas, Zn and Cu levels in cerebrum, and body weight gain of young Wistar rats. Three-day-old rats were injected (s.c.) with 5 doses (saline, Zn, Cu or Zn+Cu) for 5 consecutive days and were killed 24 h after the last dose. In the other experiment, 7-day-old rats received only 1 dose (saline, Zn or Cu) and were killed at 1, 6 or 24 h after. For the in vitro experiments, the acetylcholinesterase activity from cerebrum of 8-day-old rats was analyzed in presence of Zn or Cu (0.01 to 1 mM). Regarding the in vivo experiments, only body weight gain was decreased by 5 simultaneous administrations of Zn and Cu. The acetylcholinesterase activity from cerebrum and cerebellum and cerebral zinc and copper contents were not altered by the treatments. In vitro, Cu 0.1 and 1 mM, but not Zn, inhibited the enzyme of both cerebrum and cerebellum. The enzymatic activity from cerebrum and cerebellum homogenate was more sensitive to Cu than the enzymatic activity from S2 and S1 fractions, respectively, since less metal was necessary to inhibit the enzyme.