Stability of high-energy substrates in fast- and slow-twitch muscle: comparison of enzymatic assay of biopsy with in vivo 31P nuclear magnetic resonance spectroscopy.
Stability of high-energy substrates in fast- and slow-twitch muscle: comparison of enzymatic assay of biopsy with in vivo 31P nuclear magnetic resonance spectroscopy.
复制标题
快肌和慢肌中高能底物的稳定性：活检酶法测定与体内 31P 核磁共振波谱的比较。
DOI：
--
复制
发表时间：
1994
影响因子：
2.9
通讯作者：
K. Jeejeebhoy
中科院分区：
文献类型：
--
作者：
A. Madapallimattam;A. Cross;M. L. Nishio;K. Jeejeebhoy
本研究的目的是研究储存的肌肉样品和提取物中ATP和PCr水平的稳定性。ATP和PCr水平通过荧光分析法测量大鼠比目鱼肌、趾长伸肌和腓肠肌的冷冻钳取活组织切片在-70 ℃冰箱中储存后的（i）完整湿肌肉、（ii）冻干肌肉和（iii）冻干肌肉提取物。在活检后24小时内以及储存1 - 4周后进行检测。腓肠肌的数据进行了比较，在同一只大鼠中，通过在体内31 P NMR光谱。在活组织检查中，ATP水平是稳定的，无论储存的时间或方法如何。无论储存方法如何，与活检后24小时内进行的测定相比，PCr水平下降了13-16%，但可以通过表达与总肌酸水平相关的数据来校正冻干储存肌肉中的PCr水平。荧光测量PCr，在整个肌肉提取物的腓肠肌，在24小时内测定，从31 P NMR光谱获得的那些相媲美。我们的结论是，肌肉中的PCr水平在-70 ℃储存期间不稳定，应在肌肉活检后24小时内进行测定，以确保其值与31 P NMR获得的值相同。
The purpose of this study was to investigate the stability of ATP and PCr levels in stored muscle samples and extracts. ATP and PCr levels were measured by fluorimetric analysis in freeze-clamped biopsies of soleus, extensor digitorum longus, and gastrocnemius muscles of the rat after storage in a freezer at -70 degrees C as (i) intact wet muscle, (ii) freeze-dried muscle, and (iii) an extract of freeze-dried muscle. Assays were performed within 24 h of taking the biopsy and after variable periods of storage from 1 to 4 weeks. The data for the gastrocnemius muscles were compared with those obtained, in the same rat, by in vivo 31P NMR spectroscopy. In the biopsies, the ATP levels were stable irrespective of the duration or method of storage. The PCr levels fell by 13-16% compared with the values obtained from the assay done within 24 h of taking the biopsy, irrespective of the method of storage, but could be corrected in the freeze-dried stored muscle by expressing the data in relation to the total creatine levels. The fluorimetrically measured PCr, in whole muscle extracts of the gastrocnemius, assayed within 24 h, were comparable to those obtained from 31P NMR spectroscopy. We concluded that PCr levels in muscle are not stable during storage at -70 degrees C and should be assayed within 24 h of taking a muscle biopsy to ensure that the values are the same as those obtained by 31P NMR.