Nascimento Sérgio Ricardo Rios, Ruiz Cristiane Regina, de Oliva Samara Urban
Department of Morphology and Genetics, Developmental Biology Laboratory, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.
Human's Anatomy Department, São Camilo University Center, São Paulo, Brazil.
Anat Histol Embryol. 2019 May;48(3):228-233. doi: 10.1111/ahe.12427. Epub 2019 Jan 21.
The use of hearts from different animals as models in the experimental pharmacology and surgical clinic has led, in recent years, to an increase on interest of research with this organ. The heart's conducting system, from the septomarginal trabecula, presents several variations, which generates numerous controversies in the literature. So, the objective of the present study is to analyse the morphology of the septomarginal trabecula of bovine hearts, identifying possible macro- and microscopic variations. Thirty-four bovine hearts were analysed. Each trabecula was analysed macroscopically to obtain an anatomical description and measurements of its length and thickness. For histological and morphometric analysis, the samples were fixed in Bouin's solution and then subjected to histological processing. In all the analysed bovine hearts, the septomarginal trabecula presented itself as a smooth, tubular meaty structure of muscular consistency, with variable length and diameter. The anatomical variations observed included a trabecula with forked marginal fixation, and single septal fixation, in addition to a trabecula with extremely reduced or excessively thick caliber. The septomarginal trabecula consists of cardiac muscle fibres, connective tissue, vascular tissue and conduction myofibrils or Purkinje fibres. In the samples of smaller thicknesses, there was a predominance of connective tissue and scarce cardiac muscle tissue, whereas in the thicker samples the predominance was of cardiac striated muscle tissue. Therefore, there are significant macro- and microscopic differences between the bovine septomarginal trabecula concerning their diameter and constituent tissue, and that can lead to possible changes in cardiac physiology.
近年来，在实验药理学和外科临床中使用不同动物的心脏作为模型，引发了对该器官研究兴趣的增加。心脏传导系统，从室隔边缘小梁来看，存在多种变异，这在文献中引发了众多争议。因此，本研究的目的是分析牛心脏室隔边缘小梁的形态，识别可能的宏观和微观变异。对34颗牛心脏进行了分析。对每根小梁进行宏观分析，以获得其长度和厚度的解剖学描述及测量数据。为进行组织学和形态计量学分析，将样本固定在布安氏溶液中，然后进行组织学处理。在所有分析的牛心脏中，室隔边缘小梁呈现为一种光滑的、管状的肉质结构，具有肌肉质地，长度和直径各不相同。观察到的解剖学变异包括边缘固定呈叉状且隔侧固定单一的小梁，以及管径极度变细或过粗的小梁。室隔边缘小梁由心肌纤维、结缔组织、血管组织和传导肌原纤维或浦肯野纤维组成。在厚度较小的样本中，结缔组织占主导，心肌组织稀少，而在较厚的样本中，主要是心肌横纹肌组织。因此，牛室隔边缘小梁在直径和组成组织方面存在显著的宏观和微观差异，这可能导致心脏生理功能的潜在变化。
