不同时间内家兔尿液中乌头碱代谢产物的研究

Study on metabolites of aconitine in rabbit urine collected at different times after administration

首次采用LC／ESI—MS^n方法对乌头碱灌胃给药后不同时间内家兔尿液中的乌头碱代谢产物进对比研究。经与空白尿样对照发现，在0～4h和4～8h两个时间段，家兔尿液中除乌头碱（AC）原形外，均含有相同的代谢产物，但相对含量差别很大。通过总离子流色谱图（TIC）可以发现3个主要代谢产物（M1，M2，M4）。分别测定了各代谢产物的准分子离子及其各级碎片离子，与AC在ESI—MS^n条件下的质谱碎裂规律相比较，并参考AC体内代谢文献，推断尿液中的主要代谢产物M1为16-O-去甲基乌头碱；M2和M4的m／z均为616，为同分异构体，结构还需要进-步的确认。

LC/ESI - MS^n was used to investigate the metabolites of aconitine （AC） in rabbit urine obtained at different times after oral administration for the first time. Comparing with control rabbit urine ,the urine samples contain the same metabolites ex- cept the unchanged AC. But,the relative contents of the metabolites are widely different in urine at different times. Three metabolites （M1, M2, M4 ）were found in total ion chromatograms （TIC） of dosed urine. On the bases of MS^nfragmentation of AC and ref- erences,M~ was deduced as 16 -O -demethylaconitine. Both M2 and M4 exhibited pseudo-molecule ion [ M ＋ H] ＋ at m/z 616 and were deduced to be isomers which come from AC through demethylation and deoxidation respectively. Further research is needed for identification of their definite structures.