Buffkin D C, Hepner G, Webber M M, Davidson W D, Bassist L F, Verma R C
Cancer Res. 1978 Oct;38(10):3225-9.
The nonprotein amino acid ornithine is the major source of polyamines in mammalian physiological systems. Increased urinary polyamine levels have been demonstrated in humans with varied types of cancers. The metabolism of DL-[1-14C]ornithine monohydrochloride in rats with either Walker 256 carcinoma or chemically induced methylcholanthrene tumors was studied. Following the i.p. injection of 3 muCi[14C]ornithine per 100 g body weight, the decarboxylation of ornithine-yielding 14CO2 was monitored by utilizing the vibrating reed electrometer-ionization chamber model of Davidson and Schwabe. Tumor-bearing animals showed significant increases in ornithine metabolism as compared to controls; for Walker 256 the tumor-bearing animal to control ratio rose from 1.16 to 1.78, for methylcholanthrene implants it rose from 1.19 to 1.82, and for methylcholanthrene paintings it rose from 1.00 to 2.20. With tumor regression ornithine levels of metabolism in the tumor-bearing animals returned to base line or nearly base-line levels. These results encourage us in our attempt to develop ornithine as a biological marker of cancer.
非蛋白质氨基酸鸟氨酸是哺乳动物生理系统中多胺的主要来源。在患有各种癌症的人类中，已证实尿中多胺水平升高。研究了携带Walker 256癌或化学诱导的甲基胆蒽肿瘤的大鼠中DL-[1-14C]鸟氨酸盐酸盐的代谢。按每100克体重腹腔注射3微居里[14C]鸟氨酸后，利用戴维森和施瓦贝的振动簧片静电计-电离室模型监测产生14CO2的鸟氨酸脱羧情况。与对照组相比，荷瘤动物的鸟氨酸代谢显著增加；对于Walker 256癌，荷瘤动物与对照的比率从1.16升至1.78，对于甲基胆蒽植入物，该比率从1.19升至1.82，对于甲基胆蒽涂抹组，该比率从1.00升至2.20。随着肿瘤消退，荷瘤动物的鸟氨酸代谢水平恢复到基线或接近基线水平。这些结果鼓励我们尝试将鸟氨酸开发为癌症的生物标志物。
