Measurement of muscle protein fractional synthetic rate by capillary gas chromatography/combustion isotope ratio mass spectrometry.
Measurement of muscle protein fractional synthetic rate by capillary gas chromatography/combustion isotope ratio mass spectrometry.
复制标题
通过毛细管气相色谱/燃烧同位素比质谱法测量肌肉蛋白分数合成率。
DOI：
10.1002/bms.1200211004
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Bier,DM
中科院分区：
文献类型：
--
作者：
Yarasheski,KE;Smith,K;Rennie,MJ;Bier,DM
使用 (1-13C) 亮氨酸输注并通过制备型气相色谱 (GC)/茚三酮同位素比质谱 (IRMS) 测量骨骼肌蛋白中示踪剂的同位素丰度来测量骨骼肌蛋白分数合成率，这是费力的，并且由于 12C 污染而容易出错。本研究的目的是将传统制备型 GC/茚三酮 IRMS 方法测量的肌肉 (13C) 亮氨酸富集度与使用毛细管 GC/燃烧 IRMS 的新型连续流技术进行比较。在以不同速率向每只 Sprague-Dawley 大鼠输注 (1-13C) 亮氨酸 6-8 小时后，取出四头肌。两种方法测量的肌肉亮氨酸富集（at.% 过量）相差不到 4%，低 (13C) 亮氨酸富集（<0.03 at.% 过量）除外。此外，使用毛细管 GC/燃烧 IRMS 来评估 10 名正常年轻男性和女性输注 (1,2-13C2) 亮氨酸 12-14 小时的肌肉 (13C) 亮氨酸富集度和肌肉蛋白合成率。这种方法减少了同位素丰度测量的变异性，并给出了肌肉蛋白质合成率的估计值（0.050 ± 0.011% h−1（平均值±SEM）；范围 = 0.023‐0.147% h−1），与使用标准分析方法确定的公布值一致。通过毛细管 GC/燃烧 IRMS 测量骨骼肌蛋白中的 (13C) 亮氨酸富集，为制备型 GC/茚三酮 IRMS 提供了一种简单、可接受且实用的替代方案。
The measurement of skeletal muscle protein fractional synthetic rate using an infusion of (1‐13C)leucine and measuring the isotopic abundance of the tracer in skeletal muscle protein by preparative gas chromatography (GC)/ninhydrin isotope ratio mass spectrometry (IRMS) is laborious and subject to errors owing to contamination by12C. The purpose of this study was to compare muscle (13C)leucine enrichment measured with the conventional preparative GC/ninhydrin IRMS approach to a new, continuous‐flow technique using capillary GC/combustion IRMS. Quadriceps muscles were removed from four Sprague‐Dawley rats after each was infused at a different rate with (1‐13C)leucine for 6–8 h. Muscle leucine enrichment (at.% excess) measured by both methods differed by less than 4%, except at low (13C)leucine enrichments (<0.03 at.% excess). In addition, capillary GC/combustion IRMS was used to assess muscle (13C)leucine enrichment and fractional muscle protein synthesis rate in ten normal young men and women infused with (1,2‐13C2)leucine for 12–14 h. This approach reduced the variability of the isotope abundance measure and gave estimates of muscle protein synthesis rate (0.050 ± 0.011% h−1(mean ± SEM); range = 0.023‐0.147% h−1) that agree with published values determined using the standard analytical approach. The measurement of (13C)leucine enrichment from skeletal muscle protein by capillary GC/combustion IRMS provides a simple, acceptable and practical alternative to preparative GC/ninhydrin IRMS.