36 CORA SENNER WINKIN 



greater abruptness of the initial rise while the depression of level due 

 to vagus activity was apt to be increasingly delayed and tended to 

 appear on the crest^of the wave, somewhat similar to the effect described 

 after section of the accelerators. The precipitous fall which occurs in 

 these animals with ligated adrenals just about half as late as in intact 

 cats then appears as soon as the point of maximal pressure is gained, 

 namely, immediately after cessation of the vagus depression. 



Fig. 6. Cerebral anemia following ligation of the adrenals. Cat. 53. Arterial 

 occlusion immediately following tying off of the glands. Occlusion time, 1| 

 minutes. Time of control occlusion obtained from this animal, 3 minutes. 



Effect of the adrenal glands on the anemic rise. The marked shorten- 

 ing of the anemic response eventually obtained in all the animals in 

 which the adrenal glands had been ligated seems to isolate a further 

 factor concerned in the production of the anemic rise. Apparently the 

 great influence which the splanchnic system is able to exert on the level 

 of blood pressure under the critical conditions of anemia, is due in part 

 to the adjuvant activity of the adrenal glands. These experiments, 

 therefore, bear on the discussion of the emergency relation of the glands, 

 since apparently some involvement of the glands or some product of 

 their activity must be conceded under the extreme condition of cere- 

 bral anemia. Furthermore, some clue as to the nature of the activity 

 of the adrenals is given by inspection of the curves obtained. 



Loss of pressure. There has been noted a close parallelism between 

 the later curves obtained from all animals suffering repeated occlusion, 

 whether intact or deprived of adrenals. A failure of blood pressure 



