Program in Physical Therapy, University of Minnesota, Minneapolis, MN 55455, USA.
Am J Phys Med Rehabil. 2012 Nov;91(11):965-76. doi: 10.1097/PHM.0b013e31825f18e1.
The aim of this study was to determine the contribution of spontaneous post-stroke physical activity to skeletal muscle plasticity after stroke.
A randomized controlled study was conducted of 24 young adult male Sprague-Dawley rats assigned to three experimental groups: (1) STR-hemorrhagic stroke in the right caudoputamen; (2) SHAM-procedural control; and (3) CONT-no intervention (n = 8/group). Neurologic testing was performed before and 2 wks after stroke. Spontaneous physical activity was monitored five nights per week for 1 wk preoperatively and 2 wks postoperatively. Two weeks after stroke induction, bilateral soleus and tibialis anterior muscles were harvested. Myofiber cross-sectional areas were determined, and fiber typing was performed with immunohistochemistry.
STR animals demonstrated neurologic deficit in the contralesional hindlimb 2 wks after stroke. Quantity of spontaneous physical activity did not differ between groups within each of the week-long study intervals. No significant difference was found in fiber types or cross-sectional areas in the soleus muscle of STR vs. CONT groups. However, the tibialis anterior muscle of the contralesional hindlimbs of the STR animals showed atrophy in 2x and 1 + 2x myofibers, as well as type 1 hypertrophy.
Skeletal muscle adaptation occurs by 2 wks post-stroke in this model. It is muscle specific and appears to be influenced by factors other than spontaneous post-stroke physical activity.
本研究旨在确定自发性卒中后体力活动对卒中后骨骼肌可塑性的贡献。
对 24 只年轻成年雄性 Sprague-Dawley 大鼠进行随机对照研究，分为三组：（1）STR-右侧尾状核脑出血；（2）SHAM-程序性对照；（3）CONT-无干预（每组 n = 8）。卒中前和卒中后 2 周进行神经功能测试。在术前和术后 2 周，每周监测 5 个晚上的自发性体力活动。卒中诱导后 2 周，采集双侧比目鱼肌和胫骨前肌。测量肌纤维横截面积，并通过免疫组织化学进行纤维分型。
STR 动物在卒中后 2 周出现对侧后肢神经功能缺损。在每个为期 1 周的研究间隔内，各组之间的自发性体力活动量没有差异。STR 与 CONT 组的比目鱼肌纤维类型或横截面积没有显著差异。然而，STR 动物对侧后肢胫骨前肌的 2x 和 1 + 2x 肌纤维出现萎缩，以及 1 型肥大。
在该模型中，卒中后 2 周即发生骨骼肌适应性变化。它是肌肉特异性的，似乎受自发性卒中后体力活动以外的因素影响。
