Department of Family and Preventive Medicine, University of California, San Diego, La Jolla, California, USA.
J Strength Cond Res. 2010 Feb;24(2):522-30. doi: 10.1519/JSC.0b013e3181c8664f.
We evaluated changes in myostatin, follistatin, and MyoD messenger RNA (mRNA) gene expression using eccentric exercise (EE) and concentric exercise (CE) as probes to better understand the mechanisms of muscle hypertrophy in young women. Twelve women performed single-leg maximal eccentric (n = 6, 25 +/- 1 years, 59 +/- 7 kg) or concentric (n = 6, 24 +/- 1 years, 65 +/- 7 kg) isokinetic knee extension exercise for 7 sessions. Muscle biopsies were taken from the vastus lateralis at baseline, 8 hours after the first exercise session, and 8 hours after the seventh exercise session. In the EE group, there were no changes in myostatin and follistatin (p > or = 0.17); however, MyoD expression increased after 1 exercise bout (p = 0.02). In the CE group, there were no changes in myostatin, follistatin, or MyoD mRNA gene expression (p > or = 0.07). Differences between the EE and CE groups were not significant (p > or = 0.05). These data suggest that a single bout or multiple bouts of maximal EE or CE may not significantly alter myostatin or follistatin mRNA gene expression in young women. However, MyoD mRNA expression seems to increase only after EE.
我们使用离心运动（EE）和向心运动（CE）作为探针来评估肌肉生长抑制素、卵泡抑素和 MyoD 信使 RNA（mRNA）基因表达的变化，以更好地理解年轻女性肌肉肥大的机制。12 名女性进行了单腿最大离心（n = 6，25 ± 1 岁，59 ± 7 kg）或向心（n = 6，24 ± 1 岁，65 ± 7 kg）等速膝关节伸展运动 7 次。在基线、第一次运动后的 8 小时和第七次运动后的 8 小时，从股外侧肌采集肌肉活检。在 EE 组中，肌肉生长抑制素和卵泡抑素没有变化（p > 或 = 0.17）；然而，MyoD 表达在一次运动后增加（p = 0.02）。在 CE 组中，肌肉生长抑制素、卵泡抑素或 MyoD mRNA 基因表达没有变化（p > 或 = 0.07）。EE 和 CE 组之间的差异没有统计学意义（p > 或 = 0.05）。这些数据表明，单次或多次最大 EE 或 CE 运动可能不会显著改变年轻女性的肌肉生长抑制素或卵泡抑素 mRNA 基因表达。然而，MyoD mRNA 表达似乎仅在 EE 后增加。
