ATP and ADP hydrolysis in the kidney and liver of fish, chickens and rats

• Published in: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology 2004-12, Vol.139 (4), p.713-720
• Main Authors: Vieira, Vânia Lúcia, Morsch, Vera Maria, Lermen, Carine Luísa, da Silva, Adriane Cismoski, Tabaldi, Luciane Almeri, Schetinger, Maria Rosa Chitolina
• Format: Article
• Language: English
• Subjects: Adenosine Diphosphate - metabolism; Adenosine Triphosphate - metabolism; Animals; Calcium - pharmacology; Cell Membrane - enzymology; Chicken; Chickens - metabolism; Enzyme Inhibitors - pharmacology; Fish; Fishes - metabolism; Gallus gallus; Hydrolysis; Kidney; Kidney - enzymology; Lanthanum - pharmacology; Liver; Liver - enzymology; Membrane preparations; NTPDase; Nucleotides; Pyrophosphatases - antagonists & inhibitors; Pyrophosphatases - metabolism; Rat; Rats; Rattus norvegicus; Rhamdia quelen; Species Specificity
• ISSN: 1096-4959; 1879-1107
• DOI: 10.1016/j.cbpc.2004.08.014

We investigated NTPDase-like activity [ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases)] in liver and kidney membrane from silver catfish ( Rhamdia quelen), chicken ( Gallus gallus) and rat ( Rattus norvegicus) under different conditions and in the presence of several inhibitors. The cation concentration required for maximal activity was 0.5, 1.5 and 2.0 mM for fish, chicken and rat liver, respectively (with ATP and ADP as substrates). The maximal activity in the kidney was observed at calcium concentrations of 0.5, 2.0, 1.5 mM (ATP) and 0.5, 1.5, 1.0 (ADP) for fish, chickens and rats, respectively. The results showed that the pH optimum for all animals and for the two tissues was close to 8.0. The temperature chosen was 25 °C for fish and 36 °C for chicken and rat preparations. Ouabain had no effect on the NTPDase-like activity of fish, chickens or rats. NTPDase activity was decreased in the presence of lanthanum in the chicken (ADP) and rat (ATP and ADP) liver. In the kidney, lanthanum inhibited fish ATP and rat ATP and ADP (0.2 mM) hydrolysis. N-ethylmaleimide (NEM) had an inhibitory effect on the kidney of all species at the concentration of 3.0 mM (ADP). Orthovanadate only inhibited fish membrane NTPDase; azide only inhibited the preparation at high concentrations (10 mM) and fluoride inhibited it at 10 mM (fish and chicken) and 5 mM (rat). Trifluoperazine (0.05–0.2 mM) and suramin (0.03–0.3 mM) inhibited NTPDase at all concentrations tested. These results suggest that NTPDase-like activity shows a different behavior among the vertebrate species and tissues studied. Additionally, we propose that NTPDase1 is the main enzyme present in this preparation.