MYOCARDIAL RESPONSE TO EXERCISE DURING SENESCENCE

拟议工作的总体目标是确定是否 衰老期间的耐力锻炼将扭转与衰老相关的衰退 在心肌的细胞属性中，从而导致 改善了心肌功能。其他人则认为， 肌浆网的功能可能是导致心肌梗死的重要因素。 延缓心肌等长收缩持续时间的研究 衰老。此外，随着年龄的增加，心肌蛋白质合成明显减少。 生物体从成熟到衰老。因此，这项提案涉及 用肌浆网和蛋白质合成的检测 成年和衰老大鼠心脏的更详细信息，然后是 这两个参数对耐力反应能力的测定 锻炼身体。心肌细胞依赖于ATP的钙转运特性 对肌浆网进行生化和形态学检查 测定(1)与水解物有关的钙通量的技术 各种条件下的ATP和(2)钙离子的密度 转运ATPase，无论是在原位还是体外。心肌梗死的发生率 将估计肌动蛋白、细胞色素c和核糖体的蛋白质合成。 蛋白质。肌动蛋白和细胞色素c的mrna水平将是 量过了。肌浆网和蛋白质合成都将是 在指定时间段的耐力训练前后进行检查 在衰老过程中。离体骨的等长收缩参数 将在运动训练的每个时间点对乳头肌进行评估 以确定心肌功能是否有任何改善。这些 因此，研究将确定细胞因子的适应性 衰老过程中的心肌耐力训练与心脏功能的关系 心肌功能。以这种方式洞察这些机制 在衰老过程中参与锻炼的有益方面可能是 收获了。

The overall aim of the proposed work is to determine whether or not endurance exercise during senescence will reverse the aging-related decline in the cellular properties of the myocardium, thereby leading to an improved myocardial function. Others have suggested that the decreased function of the sarcoplasmic reticulum may be an important factor in the slowing of the isometric contractile duration of cardiac muscle with aging. Moreover, myocardial protein synthesis apparently decreases as the organism ages from maturity to senescence. Therefore, this proposal deals with the examination of the sarcoplasmic reticulum and protein synthesis in greater detail in the hearts of adult and senescent rats followed by the determination of the responsiveness of these two parameters to endurance exercise. The ATP-dependent calcium transport properties of cardiac sarcoplasmic reticulum will be examined using biochemical and morphological techniques to determine (1) calcium flux in relation to the hydrolysis of ATP under a variety of conditions and (2) the density of the calcium transport ATPase, both in situ and in vitro. The rates of myocardial protein synthesis will be estimated for actin, cytochrome c, and ribosomal proteins. The levels of mRNA for both actin and cytochrome c will be measured. Both the sarcoplasmic reticulum and protein synthesis will be examined before and after specified periods of endurance exercise training during senescence. The isometric contractile parameters of isolated papillary muscle will be assessed at each time point of exercise training in order to determine any improvements in myocardial function. These studies will therefore determine the adaptability of cellular factors of the myocardium endurance exercise during senescence in relation to myocardial function. In this manner an insight into those mechanisms involved in the benefitual aspects of exercise during senescence may be gained.