萎缩比目鱼肌钾离子通道改变对高频强直收缩疲劳性的作用

发布时间：2018-03-05 23:21

本文选题：失重模拟　切入点：尾吊　出处：《航天医学与医学工程》2005年05期 　论文类型：期刊论文

【摘要】：目的探讨萎缩比目鱼肌高频强直收缩疲劳性增加涉及细胞膜离子通道的可能机理。方法建立小鼠尾部悬吊模型模拟失重状态,用离体骨骼肌肌条灌流方法,分别观测在10mmol/L钾离子和60mmol/L钠离子灌流液灌流下,小鼠比目鱼肌高频强直收缩功能的变化。结果在生理溶液灌流下,悬吊1周组小鼠比目鱼肌高频强直收缩的最大张力(Po)与其同步对照组相比,仅有降低趋势;但是,高频强直收缩第33秒收缩张力与最大张力之比(P33/Po)却明显降低。尾部悬吊1周组小鼠比目鱼肌高频强直收缩后恢复时间短于正常对照组。与生理溶液灌流相比,高钾灌流的悬吊1周组与对照组比目鱼肌的Po均明显降低,两组P33/Po也显著降低,即疲劳性增加;低钠灌流的对照组比目鱼肌的P33/Po呈显著性降低,但悬吊组增高。在高钾灌流条件下,对照组比目鱼肌等长收缩的阈刺激电压无明显改变,而悬吊1周组则明显降低;在低钠灌流条件下,对照组和悬吊1周组比目鱼肌等长收缩阈刺激电压均显著增高。结论萎缩比目鱼肌纤维膜上K+通道的改变,可能是引起其高频强直收缩疲劳性增加的主要因素。
[Abstract]:Objective to explore the possible mechanism of the increase of high frequency constriction fatigue of atrophy soleus muscle involved in the ion channel of cell membrane. Methods the tail suspension model of mice was established to simulate weightlessness and the isolated skeletal muscle strips were perfused. The effects of 10 mmol / L potassium ion and 60 mmol / L sodium ion on the high frequency tetanic contraction of soleus muscle in mice were observed. The maximal tension of soleus muscle in the suspension group for 1 week only decreased compared with the synchronous control group. However, there was no significant difference between the two groups. The ratio of contraction tension to maximum tension of high frequency ankylosis contraction was significantly lower than that of the control group (P 33 / P). The recovery time of soleus muscle in tail suspension for 1 week was shorter than that in normal control group. Compared with physiological solution perfusion, the recovery time of soleus muscle was shorter than that of normal control group. The Po of soleus muscle in hyperkalemia group and control group decreased significantly, and the P 33% Po of soleus muscle decreased significantly in both groups, that is, fatigue increased, while that of soleus muscle in low sodium perfusion group decreased significantly. Under the condition of high potassium perfusion, the threshold stimulation voltage of isometric contraction of soleus muscle in the control group did not change significantly, while the threshold stimulation voltage decreased significantly in the suspension group for 1 week. ConclusionThe changes of K channel in the fibrous membrane of the atrophic soleus muscle may be the main factor leading to the increase of the fatigue properties of the soleus muscle in the control group and the suspension group for 1 week, and the stimulation voltage of the isometric contraction threshold of the soleus muscle is significantly higher than that of the control group.
【作者单位】：第四军医大学航空航天生理学教研室第四军医大学航空航天生理学教研室
【基金】：第四军医大学创新工程(CX02A005) 第四军医大学骨干人才(2004年度)资助
【分类号】：R85;

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