Pargyline (I) and four of its major amine metabolites, N-benzylpropargylamine (II), N-methylpropargylamine (IV), N-benzylmethylamine (VI) and pargyline N-oxide (VIII), were determined by g.l.c. after reaction with isobutyl chloroformate in a two-phase system. Pargyline and metabolite IV which form the same derivative, were separated quantitatively by liquid-liquid distribution before derivatization with isobutyl chloroformate. Also, metabolites VI and VIII form identical derivatives, and as they could not be easily separated, VIII was reduced to I before derivatization. The analytical method was applied in studies of the metabolism of pargyline in microsomes from phenobarbitone pretreated rats. The metabolism was rapid, leading mainly to the formation of II, IV, VI and VIII. 92% of the substrate was consumed during the first min of incubation at an initial substrate concentration of 100 μM (32 nmol mg−1 protein), and II, IV, VI and VIII accounted for 83% of formed metabolites. The metabolite II was further metabolized while the levels of IV, VI and VIII remained constant after 5 min. It was possible to determine 0.5 μM of pargyline, II and VI in microsomal incubations, with an r.s.d. of <5% (n = 6). N-Methylpropargylamine (IV) was positively identified and quantitated as a pargyline metabolite for the first time.
在两相系统中,使用异丁基氯甲酸酯反应后,通过气相色谱法测定了Pargyline(I)及其四种主要的胺代谢物,即N-苄基丙炔胺(II)、N-甲基丙炔胺(IV)、N-苄基甲胺(VI)和Pargyline N-氧化物(VIII)。在使用异丁基氯甲酸酯进行衍生化之前,通过液液分配定量分离了形成相同衍生物的Pargyline和代谢物IV。此外,代谢物VI和VIII形成相同的衍生物,由于难以分离,因此在衍生化之前将VIII还原为I。该分析方法应用于苯巴比妥预处理大鼠微粒体中Pargyline代谢的研究中。代谢速度很快,主要导致形成II、IV、VI和VIII。在初始底物浓度为100μM(32 nmol mg−1蛋白质)的孵育的第一分钟内,92%的底物被消耗,而II、IV、VI和VIII占形成代谢物的83%。代谢物II进一步代谢,而IV、VI和VIII的水平在5分钟后保持不变。在微粒体孵育中,可以确定0.5μM的Pargyline、II和VI,其r.s.d.小于5%(n = 6)。N-甲基丙炔胺(IV)首次被确定并定量为Pargyline代谢物。