Leeson T S
Acta Anat (Basel). 1980;108(3):374-88. doi: 10.1159/000145320.
Myocardial cells of rat atria have been studied using standard fixation and tannic acid mordanting. Cells were arranged in bundles or fascicles with little connective tissue. Fiber size varied, with complex cell junctions and in many fibers, particularly those of small diameter, no T-tubules or internal couplings were seen. Most cells, however, contained T-tubules, mainly coupled as triads at Z-lines but showing considerable variation in morphology. Direct continuity of T-tubules with the sarcolemma was demonstrated. Apparently unrelated to T-tubules and internal couplings, all cells showed the presence of peripheral couplings between sarcoplasmic reticulum and sarcolemma and, often, the subsarcolemmal element of reticulum was observed to pass internally in the sarcoplasm from a peripheral coupling. Also present were subsarcolemmal caveolae. The occasional presence within a single cell of myofibrils orientated in different planes was noted also. The findings are discussed in relation to the role of T-tubules and couplings in excitation-contraction.
已使用标准固定和单宁酸媒染法对大鼠心房的心肌细胞进行了研究。细胞成束或成束状排列，结缔组织很少。纤维大小各异，具有复杂的细胞连接，并且在许多纤维中，特别是那些小直径的纤维中，未观察到T小管或内部连接。然而，大多数细胞含有T小管，主要在Z线处作为三联体连接，但形态上有相当大的变化。证实了T小管与肌膜的直接连续性。显然与T小管和内部连接无关，所有细胞都显示出肌浆网与肌膜之间存在外周连接，并且经常观察到网状结构的肌膜下成分从外周连接向内穿过肌浆。还存在肌膜下小窝。还注意到在单个细胞内偶尔存在不同平面取向的肌原纤维。结合T小管和连接在兴奋-收缩中的作用对这些发现进行了讨论。
