El Sawalhy A, Seed J R, Hall J E, El Attar H
Department of Animal Science, Faculty of Veterinary Medicine, Moshtohour Tukh, Benha, Egypt.
J Parasitol. 1998 Jun;84(3):469-73.
Aromatic amino acid catabolism by Trypanosoma brucei evansi was investigated in vivo using C3HeB/FeJ mice. The major catabolites detected by gas chromatography in the urines of infected animals were phenylpyruvic acid, 4-hydroxyphenylpyruvic acid, and indole-3-pyruvic acid. Identity of each compound was confirmed by gas chromatography-mass spectrometry. Concentrations of catabolites in urine of infected mice were correlated with parasitemia and returned to normal following suramin treatment. Other aromatic amino acid metabolites, including indole-3-acetic acid, indole-3-lactic acid, and 4-hydroxyphenyllactic acid, were detected in urine from infected animals by gas chromatography mass spectrometry, although quantities were too low to be quantified reproducibly. Both phenylpyruvic acid and 4-hydroxyphenylpyruvic acid were also detected in urine of dogs and donkeys experimentally infected in Egypt with a recent field isolate of T. b. evansi. Tryptophan metabolites could not be assayed in dog and urine samples because formalin, which degraded the indole acids, had to be added before the samples could be imported into the U.S. Finally, concentrations of urinary catabolites during infection were correlated with the tyrosine aminotransferase activity in infected mouse sera.
利用C3HeB/FeJ小鼠在体内研究了伊氏锥虫对芳香族氨基酸的分解代谢。通过气相色谱法在感染动物尿液中检测到的主要分解代谢产物为苯丙酮酸、4-羟基苯丙酮酸和吲哚-3-丙酮酸。每种化合物的身份通过气相色谱-质谱法得以确认。感染小鼠尿液中分解代谢产物的浓度与寄生虫血症相关，苏拉明治疗后恢复正常。通过气相色谱-质谱法在感染动物尿液中检测到了其他芳香族氨基酸代谢产物，包括吲哚-3-乙酸、吲哚-3-乳酸和4-羟基苯乳酸，尽管其含量过低无法进行可重复定量。在埃及用近期从野外分离的伊氏锥虫实验感染的犬和驴的尿液中也检测到了苯丙酮酸和4-羟基苯丙酮酸。由于在将样本进口到美国之前必须添加会降解吲哚酸的福尔马林，因此无法在犬和尿液样本中检测色氨酸代谢产物。最后，感染期间尿液分解代谢产物的浓度与感染小鼠血清中的酪氨酸转氨酶活性相关。
