Effects of cadmium exposure on critical temperatures of aerobic metabolism in eastern oysters Crassostrea virginica (Gmelin, 1791).

摘要: Cadmium (Cd) and elevated temperatures are common stressors in estuarine coastal environments. Elevated temperature can sensitize organisms to the toxicity of metals such as Cd vice versa, but physiological mechanisms temperature-Cd interactions not well understood. We tested a hypothesis that interactive effects stress involve Cd-induced reduction aerobic scope an organism thereby narrowing thermal tolerance window oysters. determined prolonged exposure (50 μg l(-1)for 30 days) on upper critical metabolism (assessed by accumulation anaerobic end products L-alanine, succinate acetate), cellular energy status tissue levels adenylates, phosphagen/aphosphagen glycogen lipid reserves) oxidative damage during acute rise (20-36 °C) eastern oysters Crassostrea virginica. The (TcII) was shifted lower values (from 28 24 Cd-exposed spring both control groups winter (24 <20 °C, respectively). This indicates associated with decrease early transition partial anaerobiosis. Acute warming had no negative reserves or parameters (except adenylate content at extreme 36 led increase lesions proteins temperatures. These data show anaerobiosis (indicated products) is most sensitive biomarker temperature-induced energetically non-sustainable state oysters, whereas disturbances (i.e. decline phosphagen levels) ensue considerably higher temperatures, nearing lethal range. study long-term environmentally relevant may their sensitivity seasonal and/or global climate change polluted estuaries.