Carey G P, Kime Z, Rogers Q R, Morris J G, Hargrove D, Buffington C A, Brusilow S W
Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
J Nutr. 1987 Oct;117(10):1734-9. doi: 10.1093/jn/117.10.1734.
The essentiality of dietary arginine was examined in adult humans with three biochemical indices: plasma levels of ammonium and amino acids and urinary orotic acid excretion. Three male and two female subjects participated in the 10-d study. Subjects consumed an L-amino acid diet containing 0.74 g protein equivalent/kg body weight on d 1-5; these amino acid concentrations were doubled on d 6-10. The diet was devoid of arginine on d 3-8. Daily urine was collected and blood samples were drawn on 6 of the 10 d at 0, 0.5, 1, 2, 3 and 4 h after the breakfast meal. When arginine was removed from the diet, urinary orotic acid did not increase, in contrast to what has been reported in most other animal species tested. Plasma ammonium concentrations remained within normal limits throughout the study. A small postprandial decrease in plasma arginine concentration was observed when the arginine-deficient diet was consumed; this decline disappeared when the diet was resupplied with arginine. The results of this study suggest that over the short term the adult human's capacity for de novo arginine synthesis when fed a dietary deficiency of arginine is sufficient for the maintenance of normal cellular metabolism.
通过三项生化指标，即血浆铵和氨基酸水平以及尿乳清酸排泄，对成年人体内膳食精氨酸的必要性进行了研究。三名男性和两名女性受试者参与了这项为期10天的研究。受试者在第1 - 5天食用含0.74克蛋白质当量/千克体重的L - 氨基酸饮食；在第6 - 10天，这些氨基酸浓度翻倍。在第3 - 8天的饮食中不含精氨酸。在10天中的6天，于早餐后0、0.5、1、2、3和4小时收集每日尿液并采集血样。与大多数其他受试动物物种的报道情况相反，当饮食中去除精氨酸时，尿乳清酸并未增加。在整个研究过程中，血浆铵浓度保持在正常范围内。食用缺乏精氨酸的饮食时，观察到餐后血浆精氨酸浓度略有下降；当饮食重新补充精氨酸后，这种下降消失。这项研究的结果表明，短期内，成年人体内在膳食缺乏精氨酸时从头合成精氨酸的能力足以维持正常的细胞代谢。
