On the question of the action of muscarine and atropine on the heart

Since Schmiedeberg's publication of his classic work on muscarine and its action on the heart (Das Muscarin. Das giftige Alcaloid des Fliegenpilzes-Agaricus Muscarius L. - V. Dr. O. Schmiedeberg u. Dr. Richard Corre. 1869), a view has been established on the mechanism of action of muscarine is such that muscarine causes cardiac arrest due to irritation of the vagus nerve in the heart; in this case, cardiac arrest can be eliminated, as the above-mentioned author has shown, by the introduction of atropine, which paralyzes the endings of n. vagi. Prof. Kravkov, in his 1907 textbook Fundamentals of Pharmacology, emphasizes in particular that “the action of muscarine is concentrated on the endings n. vagi". Schmiedeberg has not changed his view on the action of muscarine and atropine to this day, which is clear from his "Grundriss der Pharmakologie" - 1909, although I produced and published in 1894 the work "On the question of the innervation of the frog heart (Neurological Bulletin and Arch. f. Anatomie u. Physiologie) could give rise to a reservation regarding the vagus nerve.