206 CORTEX 



of the medullary tissue for the maintenance of the normal 

 metabolic processes as reflected in the oxygen consumption. 



The adrenal cortical hormone, on the other hand, is either 

 itself necessary for the maintenance of the normal oxidative 

 processes in the tissues, or at least its absence makes impossible 

 the normal utilization of oxygen by the tissues. This depend- 

 ence of the metabolism on the adrenal cortical hormone has 

 been repeatedly demonstrated by the fall in the basal metabolic 

 rate which follows adrenalectomy. This fall in the metabolic 

 rate is proportional to, and is the primary cause of the fall in 

 body temperature which accompanies adrenal insufficiency. 268 

 The observed diminution in the oxygen consumption and body 

 temperature are directly proportional to the degree of adrenal 

 insufficiency. 23 ' 568 Extremely low values may be obtained in 

 the terminal stages of insufficiency (cf. Figure 10). 



A severe but non-fatal injury to the adrenals, on the other 

 hand, causes a significant and prolonged increase in the metab- 

 olism. This has been demonstrated by Marine and Bau- 

 mann 434 in rabbits and confirmed by Scott 561 in cats. This 

 temporary increase in basal metabolism is also reflected in an 

 increased body temperature and has been observed by the 

 author many times in rats, cats, and dogs immediately follow- 

 ing double adrenalectomy. 



Marine and Baumann found that the rise in the metabolic 

 rate after adrenalectomy is followed by a fall to or below the 

 normal. This occurred whether the rabbits died of adrenal 

 insufficiency or lived indefinitely due to the presence of acces- 

 sory or hypertrophied remnants of tissue left at operation. 

 The average maximum rise of metabolism following the opera- 

 tion was 23 per cent of the basal value. 



The rise in metabolism just described is produced by thyroid 

 activity for it is absent if a preliminary thyroidectomy has 

 been performed, and is reflected in a thyroid hyperplasia noted 

 after partial adrenal destruction in the cat or rabbit. This 

 hyperplasia and hyperfunction of the thyroid are probably 



