Okayama A, Ogawa Y, Goto S, Yamatodani A, Wada H, Okuno E, Takikawa O, Kido R
Department of Environmental Health & Hygiene, Osaka University Medical School, Japan.
Toxicol Appl Pharmacol. 1988 Jul;94(3):356-61. doi: 10.1016/0041-008x(88)90277-3.
Eight-week-old female Wistar rats were exposed to carbon disulfide for 6 hr a day, 5 days a week, for 12 weeks in inhalation chambers. Then the activities of the main enzymes of tryptophan metabolism (i.e., L-tryptophan 2,3-dioxygenase, indoleamine 2,3-dioxygenase, kynurenine 3-hydroxylase, kynureninase, and kynurenine aminotransferases) in their tissues were determined. The results showed that exposure to carbon disulfide caused a significant increase in the activities of kynureninase and kynurenine-2-oxoglutarate aminotransferase in the kidneys, but only a slight increase in their activities in the liver. The activities of L-tryptophan 2,3-dioxygenase and kynurenine 3-hydroxylase also tended to increase, but the increases were not statistically significant. These results suggests that the kynurenine pathway of tryptophan metabolism in the kidneys of rats exposed to carbon disulfide is activated and that the increased activities of kynurenine-2-oxoglutarate aminotransferase in the kidneys may cause the increased excretion of tryptophan metabolites after tryptophan loading as shown in an earlier study (A. Okayama, L. Fun, A. Yamatodani, Y. Ogawa, H. Wada, and S. Goto, 1987, Arch. Toxicol. 60, 460-463.
将8周龄的雌性Wistar大鼠置于吸入舱中，每周5天，每天暴露于二硫化碳6小时，持续12周。然后测定其组织中色氨酸代谢主要酶（即L-色氨酸2,3-双加氧酶、吲哚胺2,3-双加氧酶、犬尿氨酸3-羟化酶、犬尿氨酸酶和犬尿氨酸转氨酶）的活性。结果表明，暴露于二硫化碳会导致肾脏中犬尿氨酸酶和犬尿氨酸-2-氧代戊二酸转氨酶的活性显著增加，但肝脏中它们的活性仅略有增加。L-色氨酸2,3-双加氧酶和犬尿氨酸3-羟化酶的活性也有增加的趋势，但增加没有统计学意义。这些结果表明，暴露于二硫化碳的大鼠肾脏中色氨酸代谢的犬尿氨酸途径被激活，并且肾脏中犬尿氨酸-2-氧代戊二酸转氨酶活性的增加可能导致如早期研究（A.冈山、L.芬、A.山户谷、Y.小川、H.和田和S.后藤，1987年，《毒理学文献》60卷，460 - 463页）所示色氨酸负荷后色氨酸代谢产物排泄增加。
