Acrylamide (AA) is a toxicant in high-temperature processed foods and an animal carcinogen. Upon absorption, AA is metabolized to glycidamide (GA) or conjugates with glutathione (AA-GSH). Important advantages of microdialysis coupled with liquid chromatography-tandem mass spectrometry (MD-LC-MS/MS) include its minimization of potential losses during sample collection, storage and preparation, as well as an improvement in temporal resolution for toxicokinetics (TKs). We aimed to simultaneously study the TKs of AA and products of its primary metabolism using an isotope-dilution (ID) MD-LC-MS/MS method. MD probes implanted into the jugular vein/right atrium of anesthetized Sprague Dawley rats were connected to the ID-LC-MS/MS for continuous monitoring of AA, GA and AA-GSH in the blood every 15 min over 8 h following intraperitoneal AA administration (0.1 mg/kg or 5 mg/kg). AA, GA, and AA-GSH TKs followed linear kinetics: GA AUC/AA AUC = 0.11 and AA-GSH AUC/AA AUC = 0.011 at 5 mg/kg. Elimination half-life (T_e1/2) values were 2.44 ± 0.70, 4.93 ± 2.37 and 3.47 ± 1.47 h for AA, GA and AA-GSH, respectively. GA TKs reached a plateau at 3–6 h, suggesting that metabolic saturation of AA and T_e1/2 values of the analytes were prolonged with AA at 5 mg/kg. Our results demonstrate that oxidation of AA to GA overwhelmed the conjugation of AA with GSH. Our innovative MD-ID-LC-MS/MS method facilitates the simultaneous characterization of multiple TKs associated with toxicants and their active metabolites with excellent temporal resolution to capture metabolic saturation of AA to GA.

丙烯酰胺 (AA) 是高温加工食品中的有毒物质和动物致癌物。吸收后，AA 代谢为缩水甘油酰胺 (GA) 或与谷胱甘肽 (AA-GSH) 结合。微透析与液相色谱-串联质谱 (MD-LC-MS/MS) 相结合的重要优势包括最大限度地减少样品收集、储存和制备过程中的潜在损失，以及提高毒代动力学 (TKs) 的时间分辨率。我们旨在使用同位素稀释 (ID) MD-LC-MS/MS 方法同时研究 AA 的 TKs 及其主要代谢产物。植入麻醉 Sprague Dawley 大鼠颈静脉/右心房的 MD 探针连接到 ID-LC-MS/MS 以连续监测 AA，腹腔内 AA 给药（0.1 mg/kg 或 5 mg/kg）后 8 小时内每 15 分钟血液中的 GA 和 AA-GSH。AA、GA 和 AA-GSH TK 遵循线性动力学：5 mg/kg 时 GA AUC/AA AUC = 0.11 和 AA-GSH AUC/AA AUC = 0.011。消除半衰期（TAA、GA 和 AA-GSH 的_e1/2 ) 值分别为 2.44 ± 0.70、4.93 ± 2.37 和 3.47 ± 1.47 h。GA TKs 在 3-6 小时达到一个平台期，表明 AA 的代谢饱和度和分析物的T _e1/2值随着 5 mg/kg 的 AA 延长。我们的结果表明，AA 氧化为 GA 压倒了 AA 与 GSH 的共轭。我们创新的 MD-ID-LC-MS/MS 方法有助于同时表征与毒物及其活性代谢物相关的多种 TK，具有出色的时间分辨率，可捕获 AA 到 GA 的代谢饱和度。