Ogneva I V, Altaeva E G
Biofizika. 2010 Sep-Oct;55(5):918-24.
It has been shown that the modulation of the mechanical properties of sarcolemma by nifedipine may be related to the dynamics of accumulation of calcium ions under short-term rat hindlimb suspension. The basal calcium level was measured by the fluorescence probe Fluo-4AM, the transversal stiffness of different parts of the contractile apparatus and sarcolemma was estimated by atomic force microscopy, and the content of desmin was determined by gel electrophoresis with immunoblotting. It has been found that nifedipine has a protecting effect on muscle fibers under hypogravity by decreasing the degradation of desmin and proteins that determine the transversal stiffness of sarcolemma and the contractile apparatus, and the intensity of the increase in the basal calcium level. It was shown that the selective blocking of L-channels leads to an increase in the basal calcium level in intact soleus fibers. At the same time, the transversal stiffness of sarcolemma and the contractile apparatus increased. The mechanism of this increase is still unclear; however, it is assumed that it mediates the protecting action of nifedipine.
已表明，硝苯地平对肌膜力学性能的调节可能与短期大鼠后肢悬吊下钙离子积累的动力学有关。通过荧光探针Fluo-4AM测量基础钙水平，通过原子力显微镜估计收缩装置和肌膜不同部位的横向刚度，并通过免疫印迹凝胶电泳测定结蛋白含量。已发现，硝苯地平通过减少结蛋白以及决定肌膜和收缩装置横向刚度的蛋白质的降解，以及基础钙水平升高的强度，对低重力下的肌纤维具有保护作用。结果表明，L通道的选择性阻断导致完整比目鱼肌纤维基础钙水平升高。同时，肌膜和收缩装置的横向刚度增加。这种增加的机制尚不清楚；然而，推测它介导了硝苯地平的保护作用。
