Relation of the Adrenal Glands 



41 



15 (1975) 



Observations on the relation of the adrenal glands to the blood- 

 pressure response during cerebral anaemia in cats and rabbits. 



By HELEN C. COOMBS and J. M ROGOFF 



[From the Department of Experimental Medicine, Western Re- 

 serve University, Cleveland, Ohio] 



The blood-pressure response during cerebral anaemia was 

 analyzed by Pike, Guthrie and Stewart a number of years ago. 

 Recently Winkin in studying some of the nervous factors in- 

 volved in the cardio-vascular changes which take place during 

 cerebral anaemia observed that after repeated occlusions of the 

 head arteries for short periods, the curve of the anaemic rise may 

 become dissociated into two distinct parts. 



The question was raised by Winkin whether the second part 

 of this anaemic rise may not be due to increased availability of 

 some product of adrenal activity which the ' 'cardio-vascular re- 

 lations found in the mammalian organism under extreme condi- 

 tions of stress" would call forth. With this in mind, we have 

 carried out a series of experiments on cats and rabbits when : 



1. The adrenal glands are tied off*, or excised during an 

 acute experiment. 



2. The adrenal veins are clipped. 



3. The remaining adrenal is excised (one having been pre- 

 viously excised and the animal allowed to recover). 



4. One adrenal is excised and the other denervated (and the 

 medulla of it curetted out or a large part of the remaining gland 

 excised in addition to denervation) and the animal allowed to 

 recover. 



5. : Both adrenals are excised (rabbit) and the animal al- 

 lowed to recover. 



In cases 3, 4, and 5 the animals were operated upon from two 

 to four weeks before the acute experiments were performed. 

 The technique of the acute experiment was that devised by Stew- 

 art, Guthrie, and Pike in which the arteries are secured as they 

 emerge from the thorax. It is well known that in the cat and 

 rabbit, when the carotid and subclavian arteries (proximal to 

 the origin of the vertebrals) are occluded, circulation to the head 



