心律失常豚鼠和猕猴窦房结细胞特殊颗粒超微结构观察

ULTRASTRUCTURE OBSERVATION OF CYTOP-LASMIC SPECIFIC GRANULES OF SINO-ATRIAL NODE IN ARRHYTHMIC GUINEA-PIGS AND MONKEYS

用电镜对６例高钾诱发的心律失常豚鼠和猕猴窦房结进行了观察。结果显示：豚鼠窦房结合特殊颗粒的细胞以及Ｐ细胞含特殊颗粒数均比猕猴的多。正常时特殊颗粒在结细胞内多呈核端分布，心律失常时多呈核周散布或单向聚集分布，向着细胞连结和成纤维细胞突起处散布。提示窦房结细胞可形成和释放特殊颗粒，特殊颗粒可能参与结细胞的兴奋传导，是影响心率的因素之一，其在心律失常时增多是一种应急反应，具有抗心律失常的作用。

Specific granules of the cells of the sino- atrial node were observed by electronmicroscope in 6 hyperkalemia induced arrhythinlc guinea- pigs and monkeys.In summary,thenumber of cells containing the specific granules and the number of the specific granules in thePcells ofthe guinea-pigs were more than that ofthe monkeys.The specific granules were chief-ly located in the sarcoplasmic core ofthe nodal cells in the normal specimens and were scatteredin the perinuclear region or toward the conjunction of the cells and processes of the fibroblastsin the arrhythmic specimens. The result suggests that these specific granules can be formed andsecreted by the nodal cells. They may participate in the excitatory conduction of the nodalcells,and were one of the factors affecting the heart rate.Such an increase in these,specificgranules during arrhythmia may be a stress reaction and has an antiarrhythmia effect.