Institute of Immunology and Physiology, Ural Branch of Russian Academy of Sciences, 106 Pervomayskaya st, Yekaterinburg, 620049, Russian Federation.
J Muscle Res Cell Motil. 2023 Dec;44(4):299-309. doi: 10.1007/s10974-023-09651-7. Epub 2023 May 30.
Pulmonary arterial hypertension (PAH) leads to changes in the pump function of the heart and causes right-sided myocardial hypertrophy and heart failure. This study was the first to compare the contractile characteristics of the multicellular myocardial preparations of the right atrium (RA) and right ventricle (RV) of male rats from the control group (CON) and the group with monocrotaline (MCT)-induced hypertrophy at the molecular and multicellular levels. In both RA and RV in MCT-treated rats, the fraction of motile filaments and the maximum sliding velocity of actin and reconstituted thin filaments over myosin decreased, and the ratio of α-/β-myosin heavy chains (MHC) shifted towards β-MHC. In the RA strips and RV trabeculae, the maximum shortening velocity, the extent of muscle shortening, the amplitude of isometric stress, the amount of work decreased. PAH leads to a greater drop in right atrial contractility than that of the ventricle.
肺动脉高压（PAH）导致心脏泵功能发生变化，引起右心心肌肥大和心力衰竭。本研究首次从分子和多细胞水平比较了对照组（CON）和多柔比星（MCT）诱导的肥厚大鼠右心房（RA）和右心室（RV）的多细胞心肌标本的收缩特性。在 MCT 处理的大鼠的 RA 和 RV 中，运动丝的分数和肌动蛋白和重组成的薄丝相对于肌球蛋白的最大滑行速度降低，并且α-/β-肌球蛋白重链（MHC）的比例向β-MHC 转移。在 RA 条带和 RV 小梁中，最大缩短速度、肌肉缩短程度、等长张力幅度、工作量减少。PAH 导致右心房收缩力下降幅度大于心室。
