Effects of chronic growth hormone hypersecretion on intrinsic contractility, energetics, isomyosin pattern, and myosin adenosine triphosphatase activity of rat left ventricle.
Effects of chronic growth hormone hypersecretion on intrinsic contractility, energetics, isomyosin pattern, and myosin adenosine triphosphatase activity of rat left ventricle.
复制标题
慢性生长激素分泌过多对大鼠左心室内在收缩力、能量学、异肌球蛋白模式和肌球蛋白三磷酸酶活性的影响。
DOI：
10.1172/jci114737
复制
发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Mercadier,JJ
中科院分区：
文献类型：
--
作者：
Timsit,J;Riou,B;Bertherat,J;Wisnewsky,C;Kato,NS;Weisberg,AS;Lubetzki,J;Lecarpentier,Y;Winegrad,S;Mercadier,JJ
我们研究了患有生长激素（GH）分泌肿瘤的大鼠左心室的乳头状肌力学和能量学、肌球蛋白表型和atp酶活性。肿瘤诱导后18周，动物的体重急剧增加（与对照组相比增加101%），但心室重量/体重比没有变化。每横截面积归一化的乳头肌最大等距力显著增加（+42%,P < 0.05），而最大空载缩短速度没有变化。尽管异肌球蛋白明显向V3方向转移（对照组为32 +/- 5%，对照组为8 +/- 2%，P < 0.001），但仍观察到这一点。力-速度关系曲率增加（+64%,P < 0.05）表明肌肉收缩更经济，提示V3肌球蛋白参与。在快速冷冻的左心室切片上测定的总钙和肌动蛋白激活的肌球蛋白atp酶活性与荷瘤大鼠和对照组相似。碱性预孵育后，这些活性仅在荷瘤大鼠中降低，表明V3酶位点参与了总atp酶活性。这些数据表明，大鼠慢性生长激素高分泌导致心肌适应的独特模式，这使得肌肉同时改善其收缩性能和经济性，这要归功于肌球蛋白表型转化和活性酶位点数量的增加。图片
We studied papillary muscle mechanics and energetics, myosin phenotype, and ATPase activities in left ventricles from rats bearing a growth hormone (GH)--secreting tumor. 18 wk after tumor induction, animals exhibited a dramatic increase in body weight (+101% vs. controls) but no change in the ventricular weight/body weight ratio. The maximum isometric force of papillary muscles normalized per cross-sectional area rose markedly (+42%, P less than 0.05 vs. controls), whereas the maximum unloaded shortening velocity did not change. This was observed despite a marked isomyosin shift towards V3 (32 +/- 5% vs. 8 +/- 2% in controls, P less than 0.001). Increased curvature of the force-velocity relationship (+64%, P less than 0.05 vs. controls) indicated that the muscles contracted more economically, suggesting the involvement of V3 myosin. Total calcium- and actin-activated myosin ATPase activities assayed on quickly frozen left ventricular sections were similar in tumor-bearing rats and in controls. After alkaline preincubation, these activities only decreased in tumor-bearing rats, demonstrating that V3 enzymatic sites were involved in total ATPase activity. These data demonstrate that chronic GH hypersecretion in the rat leads to a unique pattern of myocardial adaptation which allows the muscle to improve its contractile performance and economy simultaneously, thanks to myosin phenoconversion and an increase in the number of active enzymatic sites.Images
登录
查看更多内容
患有生长激素产生肿瘤的大鼠的心脏形态。
影响因子：
5
作者：
Gilbert,PL;Siegel,RJ;Melmed,S;Sherman,CT;Fishbein,MC
通讯作者：
Fishbein,MC
生长激素过度分泌对大鼠组织的影响，特别是心脏和骨骼肌。
DOI：
10.1677/joe.0.0850075
发表时间：
1980
期刊：
The Journal of endocrinology
影响因子：
--
作者：
R. A. Prysor;J. Jenkins
通讯作者：
J. Jenkins
肢端肥大症的心脏大小和功能
影响因子：
37.8
作者：
James B. Martins;R. Kerber;B. Sherman;M. Marcus;J. Ehrhardt
通讯作者：
J. Ehrhardt
影响因子：
20.1
作者：
GORZA, L;PAULETTO, P;SCHIAFFINO, S
通讯作者：
SCHIAFFINO, S
大鼠心肌正性肌力与舒张的关系。
DOI：
10.1152/ajpheart.1986.250.6.h1008
发表时间：
1986
期刊：
The American journal of physiology
影响因子：
--
作者：
D. Chemla;Y. Lecarpentier;J. Martín;M. Clergue;A. Antonetti;P. Hatt
通讯作者：
P. Hatt