RESUMO
Sixteen male Suffolk lambs fed a 8 ppm Cu basal diet were randomly assigned to 2 groups: 12 copper-loaded (CL) and 4 controls (C). The CL sheep were drenched initially with 3 mg Cu/kg bw daily for a week. Every week an additional dose of 3 mg Cu/kg bw was included in the drench until signs of copper poisoning appeared; the control sheep were drenched with saline solution. The onset of copper poisoning occurred between 42 and 55 d. Food intake and body weight were recorded daily. Blood samples were collected weekly to measure the activity of the liver enzymes gamma-glutamyltransferase (gammaGT), aspartate aminotransferase (AST), sorbitoll dehydrogenase (SDH) and acid phosphatase (AF). The following changes were significantly recorded in the CL sheep in the weeks or days previous to the hemolytic crisis: higher levels of gammaGT were found on the -28th d increasing slowly but continuously until the hemolytic crisis; SDH fluctuated during the period presenting higher levels on the -28th, -14th and -7th d; AST and AF activities increased from the -14th and -7th d respectively; sharp decreases in the activities of SDH and AF at the hemolytic crisis; lower feed intake and body weight gain from the -7th d; and sheep ceased eating concentrates from the -9th d and became anoretic the day before the hemolytic crisis. Plasma copper concentration increased only the day before the hemolytic crisis. There were no changes in respiratory and heart rates, rectal temperature or rumen movements throughout the pre-hemolytic phase. The higher the amount of cumulative copper drenched, the higher was the gammaGT and AST activities. It was concluded that gammaGT followed by AST are the best enzymes to assess copper-load in sheep during the pre-hemolytic phase. Sheep fed copper-rich diets with high plasma activity of these enzymes, decreased feed consumption and subtle loss of body weight are most likely to present with a hemolytic crisis in a few days.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas/veterinária , Cobre/intoxicação , Dieta , Doenças dos Ovinos/sangue , Fosfatase Ácida/sangue , Animais , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Cobre/administração & dosagem , Cobre/sangue , L-Iditol 2-Desidrogenase/sangue , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Intoxicação/sangue , Intoxicação/veterinária , Ovinos , Doenças dos Ovinos/induzido quimicamente , Fatores de Tempo , gama-Glutamiltransferase/sangueRESUMO
Quantitative screening for red blood cell sorbitol dehydrogenase (RBC-SORD) deficiency in 111 patients with juvenile onset diabetes, 92 patients with adult onset diabetes, 42 patients with idiopathic cataracts and 192 professional blood donors was performed. A wide variability in RBC-SORD activity in controls and patients was observed. No significant differences in SORD activity either between patients with diabetes and patients with idiopathic cataracts or between diabetics with and without cataracts were observed. Whether or not there were carriers for either amorphous or hypomorphous alleles of the SORD locus in the population studied could not be defined in terms of enzymatic activity levels.
Assuntos
Catarata/enzimologia , Diabetes Mellitus/enzimologia , Eritrócitos/enzimologia , L-Iditol 2-Desidrogenase/deficiência , Programas de Rastreamento , Desidrogenase do Álcool de Açúcar/deficiência , Catarata/sangue , Diabetes Mellitus/sangue , Humanos , L-Iditol 2-Desidrogenase/sangue , Valores de ReferênciaRESUMO
Erythrocyte sorbitol dehydrogenase activity was significantly lower for 34 diabetic patients (mean +/- SD: 0.219 +/- 0.085 U min-1 g Hb-1) than for 27 normal blood donors (0.34 +/- 0.094 U min-1 g Hb-1). This finding agrees with the previous report of low sorbitol dehydrogenase activity in the lens of diabetic patients but contrasts with the data of Crabbe and collaborators (M.J.C. Crabbe, A.B. Halder, C.O. Peckar and H. Cheng, Lancet, 2: 1268-1270, 1980) who found a large variation in the levels of the diabetic population and which was not significantly different from the normal control.