Effects of accumulated 60 Co y-ray irradiation on the small molecular metabolites in rats urine

Objective To explore the effects of accumulated 60Co.Y-ray irradiation on small molecular metabolites in rats urine. Methods Ten healthy male SD rats were irradiated by 60Co.Y-rays in 5 days and the accumulated doses were 0, 0. 2, 0. 4, 0. 6, 0. 8, 1.0 Gy, respectively. The metabolites in urine of different groups were measured with I H-NMR combined with principal components analysis （PCA） and partial least square discriminate analysis （PLS-DA）. Results The metabolites in rat urine were obviously changed after irradiation. Compared with control group, the amount of acetoaeetate decreased after irradiation（t = 29. 7 -30. 7,P〈 0. 05）, but its relative level was stable when the dose increased （ P 〉 0.05 ）. Meanwhile, the relative level of hippuric acid increased（ t = 4.4 - 21.6 ,P 〈 0. 05 ） especially when the accumulated dose was higher than 1 Gy （t = 21.6, P 〈 0.05 ）. The relative level of proline, taurine and trimethylamine-N-oxide increased after irradiation with the same trend （t = 3.5 - 13.4,4. 7 - 11.5,2.9- 12.7,P〈0.05）. Conclusions The acetoaeetate, hippurie acid, proline, taurine, and trimethylamine-N-oxide may be applicable for biomarkers of accumulative irradiation on rat. Key words: Accumulated irradiation;  Urinary metabolites;  Nuclear resonance spectroscopy ; Principal component analysis