[Chen Xiaojuan; Wan Chengyan; Peng Jianhua] Minist Water Resources, Inst Hydroecol, Wuhan 430079, Peoples R China; [Chen Xiaojuan; Wan Chengyan; Peng Jianhua] Chinese Acad Sci, Inst Hydroecol, Wuhan 430079, Peoples R China; [Chen Xiaojuan; Feng Weisong; Yu Yuhe] Chinese Acad Sci, Inst Hydrobiol, Wuhan 430072, Peoples R China
The toxic effects of La3+ on Tetrahymena thermophila have been studied by microcalorimetry at 28 degrees C. The metabolic rate constant (r) and peak time were linked to the concentration of La3+. The changes of metabolic rate constant indicated that low-concentration La3+ (0-75 mg/L) had no significant effects on the metabolism of Tetrahymena cells but high-concentration La3+ (100-175 mg/L) could inhibit their metabolism. From the results obtained by cell counting and fluorescence depolarization measurements, the inhibition of metabolism resulted from the decrease in cell number and the reduction in cell membrane fluidity. According to the results, it is clear that the metabolic mechanism of Tetrahymena cells has been changed with the addition of high-concentration La3+. In addition, microcalorimetry of Tetrahymena could be a sensible, easy-to-use, and convenient method for monitoring the potential effects of rare earth elements on cells and the freshwater ecosystem.
Chen Xiaojuan; Feng Weisong; Yu Yuhe; Wan Chengyan; Peng Jianhua.Studies on the toxic effects of La3+ to Tetrahymena thermophila by microcalorimetry,BIOLOGICAL TRACE ELEMENT RESEARCH,2008,123(1-3):242-249