THE ADRENAL BODIES 203 



choline may be present in the adrenal bodies is of no special 

 functional significance. 



The lipoid substances contained in the cortex of the adrenal 

 body are possibly of considerable importance, and their 

 chemical nature may yet reveal the secretory function of the 

 cells of this part of the adrenal gland. Their presence in the 

 cells has been known to histologists and morphologists for a 

 long time, but attempts to deal systematically with their 

 chemistry are of recent date. So far as they are involved in 

 a treatment of the microscopic structure of the adrenal cortex, 

 they will be discussed in a later section of this work (p. 239). 

 At this stage it will be desirable to state what is known of these 

 substances from a more purely chemical standpoint. 



According to Frankel, the different organs of the body 

 contain different lipoids, which are characteristic for each 

 particular organ. The difference between the lipoids of 

 various organs on the one hand and the lipoids of the same 

 organ in different groups of animals vary both qualitatively 

 and quantitatively. 



Biedl has devoted special attention to the lipoids of the 

 adrenal bodies of the pig. He finds that the glands contain 

 74-61 per cent, water and 25-39 per cent, of dry substance. 

 Of this dry substance, 61-12 per cent, consists of protein, and 

 38-88 per cent, lipoids and extractives. It is pointed out that 

 since the extracts were made from the whole gland, the cortex 

 must contain a much greater proportion of lipoids. In order 

 to prove this point definitely it is proposed to investigate 

 the inter-renal body (which consists of cortex only) in the 

 Elasmobranch fishes. 



Thus we see that the adrenals must be placed among the 

 organs richest in lipoids, since a third of the total dry substance 

 is made up of these materials. Among the definite chemical 

 compounds recognized by Biedl in the adrenal extracts are 

 cholesterinpalmitate [C^H^O (C 16 H 31 0)], the cholesterin 

 ester of carnaubic acid [C 27 H 45 O (C 24 H 47 0)], and kephalin. 



According to Biedl, it appears probable that the cholesterin 

 esters are specific for each particular organ and perhaps for 

 each particular species, but not that they are to be regarded 

 as a definite secretory product of the gland. 



