Physiology. — "On the Injiuence of the rage on the frequency of 

 the action currents of the Diaphragm during its respiratory 

 Movements y ') By Dr. J. G. Dusser de Bahenne and Dr. J. B. 

 ZwAAHDEMAKEH. (Coiiimunicated by Prof. H. Zwaardemaker.) 



(Communicated at the meeting of September 29, 1923). 



In a previous paper one of iis') was able to show that the 

 frequency of tlie action current.s of the striped muscles, as lliey occur 

 in the cerebrate rigidity of the cat and in the voluntary contraction 

 in man, undergoes a distinct diminution after elimination of the 

 [iroprioceptive impulses, originating in the muscles during their con- 

 traction. The elimination of these proprioceptive impulses was pro- 

 duced by section of the posterior roois in the animal and by local 

 intramuscular injection of novocain in the human individual. 



We then investigated if this experimental fact could also be 

 established in other innervations and first of all in the diaphragm. 

 We will not dwell here on this investigation which gave us similar 

 results for this muscle as in the researches mentioned above. But 

 in the course of these investigations on the frequency of the action 

 currents of the diaphragm, we got results which gave rise to the 

 supposition that perhaps the vagi might have an influence on the 

 action currents of this muscle during its respiratory contractions. 



We, therefore, had to investigate this problem separately and 

 propose to deal in this paper with the obtained results. The question 

 to be answered, was therefore the following : Which is the frequency 

 of the action currents of the diaphragm during its respiratory con- 

 tractions before and after elimination of both vagi. 



At first we made use of the cat: later on, when we had already 

 obtained a definite answer to our question, we did another set of 

 experiments on the rabbit and could show that also in this animal 



') A preliminary communication of this paper was made at the Xl^h Inter 

 national PhysiologicalGongress at Edinburgh, 25th July 1923. 



') J. G. Dusser de Barenne, Unlersuchungen uber die Aktionströme der quer- 

 gestreiften Muskulatur bei der Enthirnungsstarre der Katze und der VVillkiirinner- 

 vation des Menschen. Skandin. Arch. f. Physiol., 1923, Vol. XLIU, (Festschrift fur 



R. TlGERSTEDT), S. 107. 



