Senescent heart compared with pressure overload-induced hypertrophy
Senescent heart compared with pressure overload-induced hypertrophy
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DOI：
10.1161/01.hyp.29.1.15
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发表时间：
1997-01-01
期刊：
影响因子：
8.3
通讯作者：
Besse, S
中科院分区：
文献类型：
--
作者：
Assayag, P;Charlemagne, D;Besse, S
虽然老年人的左心室收缩功能正常，但大鼠乳头肌的衰老与机械和肌浆网钙-三磷酸腺苷酶的改变类似于肥厚的心脏。然而，与收缩和松弛有关的其他钙调节蛋白的变化仍然未知。为了研究左心室功能和钙调节蛋白的变化，我们测定了4月龄(成年，13只)和24月龄(衰老，15只)大鼠的血流动力学和左心室Na+-钙交换蛋白(NCX)、兰尼定受体(RyR2)和肌浆网状钙ATPase(SERCA2)mRNA水平(以与Poly(A(+))mRNA归一化的密度计量学分数表示)。对于体外收缩功能，在成年大鼠(n=11)和老年大鼠(n=11)的离体心灌流过程中测量主动张力。为了比较中度高血压对血流动力学和钙蛋白的年龄依赖性影响，分别在2月龄(n=11和n=6)和22月龄(n=26和n=5)时诱发肾血管性高血压或进行假手术。老年大鼠虽然主动张力降低(4.7+/-0.4g/g心脏重量比8.3+/-0.7g/g心脏重量，但左心室收缩压和最大压力发展速率无明显变化，P
Although systolic left ventricular (LV) function is normal in the elderly, aging is associated in rat papillary muscle with mechanical and sarcoplasmic reticulum Ca2+ ATPase alterations similar to those observed in the hypertrophied heart. However, alterations in the other calcium-regulating proteins implicated in contraction and relaxation are still unknown. To investigate alterations in LV function and calcium-regulating proteins, we measured hemodynamics and Na+-Ca2+ exchanger (NCx), ryanodine receptor (RyR2), and sarcoplasmic reticular Ca2+ ATPase (SERCA2) mRNA levels (expressed in densitometric scores normalized to that of poly(A(+)) mRNA) in left ventricle from 4-month-old (adult, n=13) and 24-month-old (senescent, n=15) rats. For ex vivo contractile function, active tension was measured during isolated heart perfusion in adult (n=11) and senescent (n=11) rats. For comparison of age-dependent effects of moderate hypertension on both hemodynamics and calcium proteins, renovascular hypertension was induced or a sham operation performed at 2 (n=11 and n=6) and 22 (n=26 and n=5) months of age. In senescent rats, LV systolic pressure and maximal rates of pressure development were unaltered, although active tension was depressed (4.7+/-0.4 versus 8.3+/-0.7 g/g heart weight in adults, P