290 CORTEX 



the adrenal cortex. They believe the anisotropic substance in 

 the cortex to be free stearic and other fatty acids, as well as 

 cholesterol esters. The existence of a cannaubic acid ester as 

 claimed by Biedl 66 is questionable. With the exception of the 

 central nervous system, no organ contains as much lecithin-like 

 substances as the adrenals. 135 



The lipid content of the adrenals undergoes marked changes 

 in response to various physiological and pathological conditions, 

 but the significance of these changes is not entirely clear. 

 During muscular exercise, according to Elliott and Tuckett, 183 

 the lipids diminish in amount, reappearing during rest. By 

 feeding with cholesterol, the anisotropic fat content may be 

 markedly increased. The adrenals apparently reflect the 

 lipid content of the blood. Thus small doses of saponin which 

 increase the cholesterol content of the blood also increase the 

 amount of lipids present in the adrenals, while large doses of 

 this poison diminish the cholesterol content of both the blood 

 and the adrenals. 



The cortical lipids also undergo changes in various path- 

 ological conditions, but the significance of these changes is not 

 clear. There is a disappearance of the lipids in infectious or 

 toxic processes 78 as well as in anemia and severe hemorrhage. 

 In chronic cardio-vascular-renal disease, in inanition, and 

 cachexic conditions generally, the lipids are often increased. 156 



There has been considerable speculation regarding the role 

 which the lipids play in the adrenals. We have already con- 

 sidered (Chapter XI) the changes in the cholesterol content 

 of the blood in adrenal insufficiency and their probable relation 

 to adrenal physiology. Lipids are widely distributed through- 

 out the organism and constitute a fundamental part of the 

 architecture of all cells. It is doubtful therefore if the lipids 

 of the adrenal play the specific role which earlier writers 

 attributed to them. 



The views that the cortex is the seat of manufacture of the 

 lipids of the body, that the adrenal regulates the lipid me- 



