Reprinted from the American Journal of Physiology 

 Vol. XXXII June 2, 1913 No. II 



CARBON DIOXIDE PRODUCTION FROM NERVE FIBRES 

 WHEN RESTING AND WHEN STIMULATED; A 

 CONTRIBUTION TO THE CHEMICAL BASIS OF 

 IRRITABILITY. 1 



BY SHIRO TASHIRO 



[From the Department of Biochemistry and Pharmacology, the University of Chicago, and the 

 Marine Biological Laboratory, Woods Hole, Mass.] 



INTRODUCTION 



THERE have been two theories of the nature of conduction 

 one upheld among others by Hermann, that it was a prop- 

 agated chemical change; the other, at present the dominant view, 

 that it is a propagated physical change. 



In 1901 Professor Mathews suggested 2 that it was in the nature 

 of a coagulative wave propagated along the fibre; this coagulation of 

 the nerve colloids leading either directly or indirectly to the electrical 

 disturbance accompanying the impulse. At the time, there was no 

 evidence of chemical change in the nerve fibre, and its indefatiga- 

 bility seemed to point to an absence of metabolism. Certain facts 

 were known, however, which were difficult to reconcile with this phys- 

 ical theory. Darwin had observed that in Drosera, 3 conduction 

 occurred only if the protoplasm had oxygen; and Mathews 4 observed 

 that salts would not stimulate a nerve, or, at any rate, their power of 

 stimulation was much reduced if the nerve remained in the body for 

 a time after death, or if the nerve were brought into the salt solution 

 in an atmosphere of hydrogen. This clearly indicated a dependence 

 of^the irritability on oxygen. 



1 The preliminary report of these investigations was given in part in Bio- 

 chemical section of Eighth International Congress for applied chemistry, Sep- 

 tember, 1912. See original communications, Eighth International Congress of 

 applied chemistry, xxvi, p. 163. See also this Journal 1913, xxxi, p. xxii. 



2 Mathews: Century Magazine, 1902, pp. 783-792; Science, 1902, xl, p. 492. 



3 Insectivorous Plants, p. 57. 



4 Unpublished observations. 



