Ebisawa K, Kira Y, Koizumi T, Ito Y, Ogata E
Jpn Heart J. 1982 Sep;23(5):805-15. doi: 10.1536/ihj.23.805.
In an attempt to elucidate the characteristics of the metabolic response of the hypertrophying heart, the rates of amino acid incorporation into cardiac structural proteins were studied in female rabbit hearts in vivo by use of a pulse-label isotope (3H-lysine) method. Hypertrophy of the left ventricle was produced by applying mild aortic constriction. Structural proteins were separated from the heart excised 24 h after the pulse, and the rate of 3H incorporation was calculated as cpm. 3H/mg lysine of the protein. In the control (without aortic constriction), left ventricular structural proteins exhibited the following relative incorporation rate (the rate in actin being taken as 1.0): native tropomyosin, 2.79 +/- 0.38 (mean +/- SE, n = 5); 10S-actinin and alpha-actinin complex, 2.52 +/- 0.29; heavy chain of myosin, 2.09 +/- 0.25; light chain of myosin, 1.82 +/- 0.28; soluble protein, 1.79 +/- 0.30; and actin, 1.0. In the rabbits with aortic stenosis the rates of amino acid incorporation showed a striking increase up to 7 days after surgery, and declined to the control level by 1 month. Among the protein fractions, native tropomyosin and the light chain of myosin showed a much higher rate of isotopic incorporation during the earlier phase of the response. These results seem to indicate the presence of a unique pattern of metabolic response in cardiac muscle confronted with a workload.
为了阐明肥厚心脏代谢反应的特征，采用脉冲标记同位素（³H-赖氨酸）法，在雌性兔体内研究了氨基酸掺入心脏结构蛋白的速率。通过轻度主动脉缩窄诱导左心室肥厚。在脉冲后24小时切除心脏，分离结构蛋白，并将³H掺入率计算为每分钟计数（cpm）。³H/蛋白质中赖氨酸毫克数。在对照组（无主动脉缩窄）中，左心室结构蛋白呈现以下相对掺入率（以肌动蛋白的掺入率为1.0）：天然原肌球蛋白，2.79±0.38（平均值±标准误，n = 5）；10S-辅肌动蛋白和α-辅肌动蛋白复合物，2.52±0.29；肌球蛋白重链，2.09±0.25；肌球蛋白轻链，1.82±0.28；可溶性蛋白，1.79±0.30；以及肌动蛋白，1.0。在主动脉狭窄的兔子中，氨基酸掺入率在手术后7天内显著增加，并在1个月时降至对照水平。在蛋白质组分中，天然原肌球蛋白和肌球蛋白轻链在反应早期显示出更高的同位素掺入率。这些结果似乎表明，面对工作负荷时，心肌存在独特的代谢反应模式。
