HPLC-MS/MS methods for the quantitative analysis of 5-oxoproline (pyroglutamate) in rat plasma and hepatic cell line culture medium.

摘要: 5-Oxoproline (5-OP; pyroglutamate) is an intermediate in the biosynthesis of endogenous tripeptide glutathione and has been seen to be elevated biofluids tissues rats following administration glutathione-depleting hepatotoxic xenobiotics such as acetaminophen (paracetamol), bromobenzene ethionine. As 5-OP a potential biomarker for hepatotoxicity HPLC-MS/MS methods have developed its quantification vitro cell culture media rat plasma. For lower limit (LLOQ), defined lowest concentration on calibration curve, was 10 ng/ml. Minimal carry over observed between injections (less than 5% at all concentrations examined), precision accuracy were generally better 20% within day analyses. plasma LLOQ 50 ng/ml obtained. Carry less concentrations, batch 20%. The linear both sample types from up 1 μg/ml. samples obtained subjected chronic hepatotoxin methapyrilene, not increase significantly any time point compared controls. also determined human liver epithelial (THLE) cells transfected with cytochrome P450 2E1 (THLE-2E1). Following exposure THLE-2E1 acetaminophen, large increases observed, which correlated reduced cellular content toxicity. These results show that LC-MS/MS can used perform rapid, sensitive, quantitative determination vivo will enable additional investigations into utility drug-induced injury.