ACTION OF CERTAIN DRUGS 287 



of emotion and of physical exertion and even prepares 

 the way for gross muscular activity in that it increases 

 the capacity of the muscles to use glycogen (Cannon) ; 

 and most significant of all, adrenin facilitates the elimi- 

 nation of the acid by-products of muscular action. 

 Any agent, therefore, that controls the output of ad- 

 renin controls proportionally the conversion of energy into ' 

 heat and motion. 



If opium acts directly on the central battery the 

 brain so that its energy cannot be mobilized to , 

 drive the various organs of the body, one would infer 

 that through its action on the brain, opium must pre- 

 vent the histologic changes produced by kinetic stimuli. 

 The truth of this inference is strikingly evidenced by 

 experiments in which rabbits were given large doses of 

 morphin either before or immediately after receiving 

 doses of diphtheria toxin. Histologic examination of 

 the brain, the adrenals and the liver of each of these 

 animals showed that the morphin had almost wholly 

 prevented the histologic changes which previous ex- 

 periments had shown to be caused by diphtheria toxin 

 alone. 



In studying the effect of morphin on the H-ion con- 

 centration of the blood, we found that deep narcoti- 

 zation does not change the normal alkalinity of the 

 blood at least not until the stage of asphyxia in 

 fatal cases ; that in a morphinized animal psychic and 

 traumatic stimuli cause neither the clinical nor his- 

 tologic changes nor the degree of acidosis normally 

 associated with a comparable degree of kinetic stimu- 

 lation of like type ; but that the administration of 

 morphin after the H-ion concentration of the blood 



