pH heterogeneity during exercise in localized spectra from single human muscles.
pH heterogeneity during exercise in localized spectra from single human muscles.
复制标题
运动期间单个人体肌肉局部光谱中的 pH 异质性。
DOI：
10.1152/ajpcell.1993.265.5.c1332
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Goelman,G
中科院分区：
文献类型：
--
作者：
Vandenborne,K;Walter,G;Leigh,JS;Goelman,G
我们研究了运动过程中骨骼肌的pH异质性，用31P核磁共振观察，是否代表肌纤维类型的异质性。本地化的光谱同时收购比目鱼肌，内侧和外侧腓肠肌使用多volumetric定位技术，阿达玛光谱成像（HSI）技术。非选定区域对局部体积的污染<5%。从未经训练的受试者和一小群运动员的小腿肌肉中获得了HSI局部光谱。两个跖屈运动方案实施：“最大”的高频率协议和“稳态”协议在低收缩频率（0.25 Hz）。pH异质性，观察到在两个运动方案中的局部光谱的单个肌肉，如由大Pi线宽。在最大运动期间，Pi谱线宽度比磷酸肌酸谱线宽度宽三倍，覆盖整个pH单位。在稳态运动期间，在三个受试者中，Pi峰清楚地分解成两个不同的峰，一个在低pH值下，一个在高pH值下。由于在两种运动方案期间在单个肌肉的局部光谱中观察到pH异质性，因此它最有可能反映纤维类型之间的代谢异质性。
We investigated whether pH heterogeneity in skeletal muscle during exercise, observed with 31P nuclear magnetic resonance, represents muscle fiber type heterogeneity. Localized spectra were simultaneously acquired from the soleus, medial, and lateral gastrocnemius using a multivolume localization technique, the Hadamard spectroscopic imaging (HSI) technique. Contamination of nonselected regions to the localized volumes was < 5%. HSI-localized spectra were obtained from the calf muscles of untrained subjects and a small group of athletes. Two plantar flexion exercise protocols were implemented: a "maximal" high frequency protocol and a "steady-state" protocol at low contraction frequency (0.25 Hz). pH heterogeneity was observed in localized spectra of single muscles during both exercise protocols, as indicated by the large Pi line width. During maximal exercise the Pi line width was up to three times wider than the phosphocreatine line width, covering an entire pH unit. During the steady-state exercise, in three subjects the Pi peak clearly resolved into two distinct peaks, one at low pH and one at high pH. As pH heterogeneity was observed in localized spectra of single muscles during both exercise protocols, it most likely reflects the metabolic heterogeneity between fiber types.