Summary
On application of acetylcholine (ACh) to the excised arrested atria of the dog's heart we found:
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1.
The membrane resistance is reduced, simultanously the resting potential is increased.
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2.
Depolarisation is observed if the resting potential is increased above 110 mV by anelectrotonic pulses. The equilibrium potential for the action of ACh was found to be at about 102 mV.
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3.
The equilibrium potential diminishes with increasing external potassium concentration and fits well to the characteristic of a potassium potential.
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4.
It is concluded that the mechanism of the ACh effect is a specific increase of the membrane permeability to potassium ions.
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Ausgeführt mit Mitteln der Rockefeller Foundation und der Deutschen Forschungsgemeinschaft.
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Trautwein, W., Dudel, J. Zum Mechanismus der Membranwirkung des Acetylcholin an der Herzmuskelfaser. Pflugers Arch. 266, 324–334 (1958). https://doi.org/10.1007/BF00416781
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DOI: https://doi.org/10.1007/BF00416781