PHYSIOLOGY OF CORTICAL INSUFFICIENCY 169 



tion of these activities probably depletes the residual supply 

 of hormone still present in the body of the adrenalectomized 

 animal. The fact that animals survive for sometime after 

 adrenalectomy indicates either that their life is maintained 

 during this period by the supply of hormone left in the tissues 

 at operation, or that these tissues can carry on their activities 

 for some time without the hormone. In either case, excessive 

 activity of any kind will either deplete the store of available 

 hormone or hasten the ultimate collapse of the organism. We 

 should expect therefore that all influences tending to stimulate 

 the activity of the organism should hasten the onset and ag- 

 gravate the insufficiency of the adrenalectomized animal. 



Although hypersensitive to many extraneous and toxic agen- 

 cies, animals in adrenal insufficiency react sluggishly or not at 

 all to many stimulants. In the moribund cat, as Elliott 177 

 showed, there is an apparent paralysis of the vaso-motor 

 and cardio-accelerator nerves. Other nerves react in an ap- 

 proximately normal manner. Thus nicotine has no pressor 

 action in cats dying of cortical insufficiency even after pre- 

 liminary atropinization. 180 This apparent paralysis of the 

 vaso-motor nerves is actually due to a change in the non- 

 striated muscle for pituitary extract and barium chloride have 

 little or no effect on the blood pressure. Epinephrine, how- 

 ever, still causes pressor and cardio-accelerator effects. The 

 vaso-motor nerves thus appear to be paralysed because the 

 muscle cannot respond to their excitatory impulses. Hence 

 stimulation of the splanchnics or injection of nicotine cause 

 little rise in blood pressure. As Elliott pointed out, the paraly- 

 sis of the vaso-motor nerves is not due to shock for in moderate 

 shock there is little paralysis. 



It is not surprising that the physiological response of animals 

 in adrenal insufficiency should be less pronounced than it is in 

 normal animals. In insufficiency we are dealing with an ani- 

 mal, the vital processes of whose organs and tissues are at a 



