Acute effect of sublethal ammonia concentrations on common carp ( Cyprinus carpio L.). II. Effect of ammonia on blood plasma transaminases (GOT, GPT), G1DH enzyme activity, and ATP value

Abstract

Effects of different ammonia concentrations (20–2000 μg NH 3l −1) on GOT, GPT and G1DH enzyme activities, and ATP level in blood plasma of common carp were studied under four sets of conditions: (1) t = 20 °C, O 2 = 2.80 mg l −1, pH = 9.0; (2) t = 25 °C, O 2 = 2.80 mg l −1, pH = 9.0; (3) t = 25 °C, O 2 = 8.18 mg l −1, pH = 9.0; (4) t = 25 °C, O 2 = 8.18 mg l −1 pH = 9.5. Effects of ammonia during the 96-h treatment were significantly increased blood serum GOT, GPT and G1DH activities, as well as decreased ATP level independent of environmental conditions. Increases were as high as 300–400%. These values differed significantly at higher temperature and pH, and at lower oxygen levels. The enzyme GPT was very sensitive to environmental changes. The potential role of sublethal ammonia concentrations in the pathogenesis of gill necrosis in carp is discussed.