Abstract
Purpose
The formation of pyrrole adducts might be responsible for peripheral nerve injury caused by n-hexane, but there is not an effective biomarker for monitoring occupational exposure of n-hexane. The current study was designed to investigate the changes of pyrrole adducts in serum and urine of rats exposed to 2,5-hexanedione (2,5-HD) and analyze the correlation between pyrrole adducts and 2,5-HD.
Methods
Two groups of male Wistar rats (n = 8) were administered a single dose of 200 and 400 mg/kg 2,5-HD (i.p.), and another two groups (n = 8) were given daily dose of 200 and 400 mg/kg 2,5-HD (i.p.) for 5 days. Pyrrole adducts and 2,5-HD in serum and urine were determined, at different time points after dosing, using Ehrlich’s reagent and gas chromatography, respectively.
Results
The levels of pyrrole adducts in serum accumulated in a time-dependant manner after repeated exposure to 2,5-HD, while pyrrole adducts in urine, and 2,5-HD in serum and urine were kept stable. The half-life times (t 1/2) of 2,5-HD and pyrrole adducts in serum were 2.27 ± 0.28 and 25.3 ± 3.34 h, respectively. Furthermore, the levels of pyrrole adducts in urine were significantly correlated with the levels of 2,5-HD in serum (r = 0.736, P < 0.001) and urine (r = 0.730, P < 0.001), and the levels of pyrrole adducts in serum were correlated with the cumulative dosage of 2,5-HD (r = 0.965, P < 0.001).
Conclusion
The results suggested that pyrrole adducts in serum and urine might be markers of chronic exposure to n-hexane or 2,5-HD.
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Acknowledgments
This research was supported by grants from Doctoral Fund of Ministry of Education of China (20120131110058) and National Natural Science Foundation of China (81373044).
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Yin, HY., Guo, Y., Song, FY. et al. Toxicokinetic study of pyrrole adducts and its potential application for biological monitoring of 2,5-hexanedione subacute exposure. Int Arch Occup Environ Health 87, 655–662 (2014). https://doi.org/10.1007/s00420-013-0907-4
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DOI: https://doi.org/10.1007/s00420-013-0907-4