LEUCINE TRNOVR RATS W/ NEPHROTIC SYNDROME SUGGEST BODY PROTEIN CONSERVATION

患有肾病综合征的亮氨酸 TRNOVR 大鼠建议保护身体蛋白质

• 批准号: 6336811
• 负责人: VICTORIA S LIM
• 金额: $ 0.6万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2001-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6336811
• 关键词: Mammalia; aging; biological products; biomedical resource; liver; musculoskeletal system; spectrometry

Whole body leucine flux was measured in eight patients with nephrotic syndrome and in five normal subjects by primed-constant intravenous infusion of L-[l-13C]leucine. Plasma enrichment of 13C leucine and 13CKIC were measured by gas chromatography/mass spectrometry and exhaled 13CO2 by isotope ratio mass spectrometry. All parameters of leucine flux, including the rates of leucine oxidation, leucine release from protein degradation and, to a lesser extent, leucine incorporation into protein, were reduced in the nephrotic patients. The values (means (SD, umol/kg/hr) of the different parameters in the nephrotic patients and the controls were Leucine derived from protein degradation, 99(6 and 117(12 (p=0.007); leucine oxidation rate 15(7 and 22(3, (p=0.04) the rate of leucine incorporationinto whole body protein, 8484+10 and 95+6, (p=0.04), and net leucine balance which is the difference between the rates of protein synthesis and degradation was -15+7 and -22+3, (p=0 .04). Th e negative values are due to the fact that measurements were made after a 12 hr fast. Protein turnover rate, calculated from leucine flux, were 3.9+0.4 and 4.7+0.3 g/kg/day in the nephrotic and the control grops (p=0.007). Nitrogen balance, measured only in the nephrotic patients, showed a mean positive balance of 0.5 g/day. For days prior to study the patients ingested a controlled diet consisting of 0.84 g protein/kg/d and 33.3(9 Kcal/kg/day. Thus, at this level of protein/energy intake, nephrotic patients maintained nitrogen balance perhaps because of a metabolic adaptation that resulted in a down regulation of protein degradation and amino acid oxidation rates.

在八名患者中测量了全身亮氨酸通量 肾病综合征，在五个正常受试者中由底漆恒定受试者 L- [L-13C]亮氨酸的静脉输注。 血浆富集13c 通过气相色谱/质量测量亮氨酸和13ckic 通过同位素比率质谱法呼出光谱和呼气13CO2。 亮氨酸通量的所有参数，包括亮氨酸的速率 氧化，亮氨酸从蛋白质降解和较小的 程度，将亮氨酸掺入蛋白质中，降低了 肾病患者。 值（均值（SD，UMOL/kg/hr）的值 肾病患者和对照组的不同参数为 从蛋白质降解中得出的亮氨酸，99（6和117（12（p = 0.007）； 亮氨酸氧化速率15（7和22（3，（p = 0.04）亮氨酸的速率 掺入全身蛋白质，8484+10和95+6，（p = 0.04），并且 净亮氨酸余额是率的差额 蛋白质合成和降解为-15+7和-22+3，（p = 0 .04）。 Th e负值是由于进行了测量的事实 快速速度12小时后。 蛋白质周转率，根据亮氨酸计算 通量为3.9+0.4和4.7+0.3 g/kg/kg/day，在肾病中， 控制触点（p = 0.007）。 氮平衡，仅在 肾病患者的平均正平衡为0.5 g/天。 为了 研究前几天，患者摄入了控制饮食的受控饮食 0.84 g蛋白/kg/d和33.3（9 kcal/kg/day。因此，在此水平上 蛋白质/能量摄入，肾病患者保持氮平衡 也许是由于代谢适应导致下降 调节蛋白质降解和氨基酸氧化速率。