Hiramatsu T, Cortiella J, Marchini J S, Chapman T E, Young V R
School of Science, Massachusetts Institute of Technology, Cambridge 02142-1308.
Am J Clin Nutr. 1994 Aug;60(2):207-15. doi: 10.1093/ajcn/60.2.207.
The effects of removing proline from the diet on plasma leucine and proline kinetics were investigated. After a 1-wk control period, during which young adult men received a diet containing a complete L-amino acid mixture, seven subjects were given for 4 wk a diet devoid of proline (group 1); six received a diet devoid of proline, arginine, aspartate, glutamate, and serine (group 2); and seven continued with the complete diet (group 3). At the end of the control and 4-wk periods subjects were given a continuous, (3-h fast, 5-h fed) intravenous infusion of L-[1-13C]leucine and L-[5,5-2H]proline. Plasma proline was reduced significantly, especially during the fed state, in groups 1 and 2 after the 4-wk diet periods. Small but statistically significant (P < 0.05) reductions occurred in nonoxidative leucine disappearance and leucine appearance during the fasted state in group 2. Proline fluxes decreased by approximately 50% in fasted and fed states in groups 1 and 2. Mean de novo proline synthesis during the fasted state declined markedly (P < 0.05) after 4 wk in groups 1 and 2.
研究了从饮食中去除脯氨酸对血浆亮氨酸和脯氨酸动力学的影响。在为期1周的对照期内，年轻成年男性摄入含完整L-氨基酸混合物的饮食，之后，7名受试者接受了为期4周的无脯氨酸饮食（第1组）；6名受试者接受了无脯氨酸、精氨酸、天冬氨酸、谷氨酸和丝氨酸的饮食（第2组）；7名受试者继续摄入完整饮食（第3组）。在对照期和4周试验期结束时，受试者接受连续的（3小时禁食、5小时进食）静脉输注L-[1-¹³C]亮氨酸和L-[5,5-²H]脯氨酸。在4周饮食期后，第1组和第2组的血浆脯氨酸显著降低，尤其是在进食状态下。第2组在禁食状态下非氧化亮氨酸消失和亮氨酸出现出现了小幅度但具有统计学意义（P<0.05）的降低。第1组和第2组在禁食和进食状态下脯氨酸通量均下降了约50%。第1组和第2组在4周后禁食状态下的平均脯氨酸从头合成显著下降（P<0.05）。
