Abstract:

¹H NMR spectroscopy and pattern recognition method were used to assess acute biochemical effects of light rare earths. Male Wistar rats were treated with both La(NO₃)₃ and Ce(NO₃)₃ at doses of 2,10 and 50 mg/kg body weight. Serum samples from the rats dosed with the two kinds of light rare earths were gained after 48 h and analyzed by 600 MHz ¹H NMR spectra. Each NMR spectra was data-processed to provide 238 intensity-related descriptors as input coordinates in a multidimensional space and analyzed by pattern recognition method. Many low-molecular weight metabolites were identified by ¹HNMR spectra of rat serum. An increase in ketone bodies,creatinine,lactate,succinate and various amino acids(valine,leucine and glutamine) were found from the higher doses(10 and 50 mg/kg body weigh) of rare earths-treated groups,together with a decrease of glucose in the serum from Ce(NO₃)₃-dosed groups. Those results may mean that high-dosage of La and Ce impair the specific region of liver. The similar toxicities with various mechanisms for La and Ce were implicated by NMR-based metabonomic approach. Ce(NO₃)₃ exhibited a higher toxicity than La(NO₃)₃ at the same doses.

Key words: Light rare earth; Serum; Nuclear magnetic resonance(NMR); Pattern recognition; Biochemical effects