Bouvagnet P, Mairhofer H, Leger J O, Puech P, Leger J J
Institut National de la Santé et de la Recherche Médicale, Inserm U 300 LPM2, Faculté de Pharmacie, Montpellier, France.
Basic Res Cardiol. 1989 Jan-Feb;84(1):91-102. doi: 10.1007/BF01907006.
All fibers in three normal, four dilated, and two ischemic human ventricles were classified according to their myosin content using three sets of monoclonal antibodies each specific for one myosin heavy chain isoform (alpha, beta and beta'). Numerous fibers contained only beta myosin heavy chain (denoted as beta fibers), others contained either alpha and beta, or beta and beta' myosin heavy chain (denoted as alpha beta and beta beta' fibers, respectively). The percentages of alpha beta fibers were systematically determined along the walls of seven homologous regions of the ventricular myocardium. In all ventricles, there was an alpha beta-fiber transmural gradient, with less alpha beta fiber in the subendocardium than in the subepicardium. More alpha beta fibers were found in the right than in the left ventricular wall but there was no difference between the mid-portion and the apex of the free wall of each ventricle. The diseased ventricles contained a lower alpha beta fiber percentage than the normal hearts. beta beta' fibers were very rare in the normal ventricles (less than 5%) and almost inexistent in pathological hearts. The correlation between the mean alpha beta fiber percentages of the diseased hearts and their cardiac indices (r = 0.88, P less than 0.05) suggests that the small amount of alpha myosin distributed in a large number of ventricular fibers could play a role in the contractile performance of the heart. In conclusion, this study provides evidence for 1) an alpha beta fiber transmural gradient, and 2) a lower alpha myosin ratio in diseased than in normal human ventricle.
使用三组分别对一种肌球蛋白重链异构体（α、β和β'）具有特异性的单克隆抗体，根据肌球蛋白含量对取自三个正常、四个扩张型和两个缺血性人类心室的所有纤维进行分类。许多纤维仅含有β肌球蛋白重链（记为β纤维），其他纤维则含有α和β或β和β'肌球蛋白重链（分别记为αβ和ββ'纤维）。系统地测定了心室心肌七个同源区域壁上αβ纤维的百分比。在所有心室中，均存在αβ纤维的透壁梯度，心内膜下层的αβ纤维比心外膜下层少。右心室壁中的αβ纤维比左心室壁中的多，但每个心室游离壁的中部和心尖之间没有差异。患病心室的αβ纤维百分比低于正常心脏。ββ'纤维在正常心室中非常罕见（少于5%），在病理心脏中几乎不存在。患病心脏的平均αβ纤维百分比与其心脏指数之间的相关性（r = 0.88，P < 0.05）表明，分布在大量心室纤维中的少量α肌球蛋白可能在心脏的收缩性能中起作用。总之，本研究为1）αβ纤维的透壁梯度和2）患病人类心室中α肌球蛋白比例低于正常心室提供了证据。
