氣相層析質譜法測定不同代謝性壓力狀態下老鼠血液中皮質固酮的濃度

Abstract

本研究以氣相層析質譜儀(GC-MS)，配合離子選擇偵測法(SIM)提供了一個簡單、高靈敏度的方法來偵測老鼠血液中皮質固酮的含量。老鼠的血液經過乙酸乙酯的萃取後，利用pentafluorobenzyloxime -trimethylsilyl (PFBO-TMS)為衍生試劑將皮質固酮衍生進行測量，並根據質譜譜峰選取m/z = 316, 648, 663, 678作為選擇性離子偵測法的主要譜峰來進行定性定量的工作。利用此法可將皮質固酮的偵測極限降至0.1 pg。實驗中並發現，當正常老鼠經接受類葡萄糖的藥物2-DG注射後，其血液中皮質固酮的濃度，隨著注射藥物量增加，而有明顯增加的趨勢。且在投予中藥柏子仁後，亦觀察到老鼠血液中皮質固酮濃度有增加的趨勢。A simple, highly sensitive and specific method based on gas- chromatography-selected ion monitoring (SIM) mass spectrometry has been developed for the quantitation of corticosterone in rat and mice plasma. After extraction of the plasma with ethyl acetate, the residue was trimethy-silylated with pentafluorobenzyl hydroxylamine-trimethyl- silyl (PFBO-TMS). Detection of the derivatives was accomplished by a quadruple mass spectrometer in the selected ion monitoring mode (m/z of 316, 648, 663 and 678). The detection limit of the assay was 0.1 pg on column. The results show that in the plasma of non-stressed animals only minor amounts of corticosterone were found; whereas in the plasma of stressed animals, it was dramatically increased. And we also found that when the animals were treated with Thujae orientails semen, the concentration of corticosterone in plasma was enhanced. The method developed here can be used to examine corticosterone levels as a marker of stress in rats and mice and may also be used for estimation of the effect of medications.