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最近业已阐明,老年人的心脏无论在形态、代谢和功能各方面均与青壮年人的心脏有相当差别,其背景是和心肌细胞老化有关。Meerson称老年心的特征为心肌耗损的复合体。随着增龄,心肌出现心肌细胞肥大、胶原纤维增生、蛋白合成能力降低;DNA、RNA减少以及DNA/RNA比值升高;线粒体氧化磷酸化下降等等,无论是形态还是功能方面均发生多样变化。最近用超声波、核放射性物质等非损伤性方法研究老年心的功能,结果证明安静时左室收缩功能、心搏出量和舒张期容量均在正常范围之内;但在运动负荷时,其工作量或氧消耗量均随增龄呈直线下降,从而提示心脏的贮备能力不足。循环调节机理也随增龄发生变化,安静时交
Recently, it has been clarified that the heart of the elderly is quite different from the heart of young adults in terms of morphology, metabolism and function, and its background is related to the aging of cardiomyocytes. Meerson said the elderly heart is characterized by a complex of myocardial depletion. With aging, myocardial hypertrophy, decreased collagen synthesis, decreased protein synthesis, decreased DNA and RNA, increased DNA / RNA ratio, decreased mitochondrial oxidative phosphorylation, etc., both in morphological and functional changes . Recently, the non-invasive methods such as ultrasound and nuclear radioactive substances were used to study the function of the elderly heart. The results showed that left ventricular systolic function, stroke volume and diastolic volume were within the normal range at rest. However, during exercise load, Volume or oxygen consumption decreased linearly with age, suggesting that the heart’s reserve capacity is insufficient. Circulatory regulation also changes with age, pay when quiet