Dangman K H, Dresdner K P, Michler R E
Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Cardiovasc Res. 1988 Mar;22(3):204-12. doi: 10.1093/cvr/22.3.204.
Preparations of baboon cardiac tissue were studied using standard microelectrode and double barrelled potassium ion selective microelectrode techniques. Transmembrane action potentials were recorded from Purkinje fibres and from atrial and ventricular muscle cells. Purkinje fibres were impaled frequently on the ventricular septum but were sparse on the endocardium of the free wall. Purkinje fibres had longer action potential durations than ventricular muscle cells, and endocardial muscle cells had longer action potential durations than epicardial muscle cells. Tissue bundles resembling the false tendons of the canine heart were found in the ventricles. Most of these false tendons consisted of ventricular muscle as indicated by transmembrane action potentials. On rare occasions, false tendon preparations were studied in which the cells had action potentials similar to those of canine Purkinje fibres. In these preparations, normal automaticity occurred from maximum diastolic potentials greater than or equal to -85 mV. Intracellular potassium activity in the baboon ventricular muscle cells was 96(3) mmol.litre-1 (mean(SEM), n = 32), which is lower than that reported for canine tissues but higher than that reported for feline or rabbit tissues. It is concluded that, although the cellular electrophysiology of primate and canine cardiac tissues is superficially similar, consistent and perhaps important differences do occur.
采用标准微电极和双管钾离子选择性微电极技术研究了狒狒心脏组织标本。记录了浦肯野纤维以及心房和心室肌细胞的跨膜动作电位。浦肯野纤维常被刺入室间隔，但在游离壁的心内膜上分布稀疏。浦肯野纤维的动作电位时程比心室肌细胞长，心内膜肌细胞的动作电位时程比心外膜肌细胞长。在心室中发现了类似犬心脏假腱的组织束。如跨膜动作电位所示，这些假腱大多由心室肌组成。偶尔也会研究一些假腱标本，其中细胞的动作电位与犬浦肯野纤维的相似。在这些标本中，最大舒张电位大于或等于 -85 mV时会出现正常的自律性。狒狒心室肌细胞内的钾活性为96(3) mmol·升-1（平均值(标准误)，n = 32），低于犬组织的报道值，但高于猫或兔组织的报道值。得出的结论是，尽管灵长类和犬类心脏组织的细胞电生理表面上相似，但确实存在一致且可能重要的差异。
