212 J. J. Christian 



thefirst two, probably the first, is a major secretory product of the cortex, 

 presumably of the zona fasciculata-reticiilaris of house mice, rats, and very 

 possibly other rodents (Bush, 1953; Wilson ei al., 1958), and to these must 

 be added dehydroepiandrosterone, which is now known to account for half 

 of the steroid product of the adrenal cortex of human beings (VandeWiele 

 and Lieberman, 1960) . These steroids, as a group, are very weak androgens 

 with insufficient activity to maintain the seminal vesicles and ventral 

 prostate in hypophysectomized mice (Bahn et al., 1957), although they 

 evidently are sufficiently androgenic to produce histologically detectable 

 changes in the epithelium of these organs, if not in changes in gross weight 

 (Davidson and Moon, 1936; Lostroh and Li, 1957), and evidently, if they 

 are secreted in large enough ciuantities, they can produce masculinization 

 in humans (Dorfman and Shipley, 1956). In addition, Howard (1959) has 

 shown that these weak androgens are more strongly androgenic if their 

 activity is measured in terms of other assays, such as stimulation of the 

 preputials and os penis. However, the C19 steroids with weakly androgenic 

 activity, as measured by their ability to stimulate growth of the prostate 

 or capon comb, can inhibit the secretion of gonadotropins in rats, especially 

 in immature animals (author's italics) , although it has been shown that the 

 carbohydrate-active corticoids are incapable of producing this effect 

 (Byrnes and Shipley, 1950; Byrnes and Meyer, 1951; Wilson et al., 1958). 

 Therefore, it is possible that an increased secretion of these androgens 

 steroids by the adrenal cortex in mice and rats can account, at least in part, 

 for the suppression of reproduction commonly associated with circum- 

 stances which increase the secretion of ACTH and carbohydrate-active 

 corticoids, as described by Selye (1939). 



These, in brief, are the actions of the important adrenal cortical hor- 

 mones. Many questions remain unanswered regarding the functions of the 

 cortical hormones, especially wath respect to their relationships to each 

 other and to other endocrines, such as the thyroid and pancreatic islets. 

 The carbohydrate-active corticoids in many respects are antagonistic to 

 insulin and probably suppress thyroid activity, but these topics will not be 

 dealt with here. The actions already listed are the major activities of the 

 cortex which will enable an interpretation to be made of, as well as to 

 anticipate, the results in other species. All the above effects have been 

 duplicated by injecting adrenocorticotropin into intact mammals and 

 thereby stimulating an increased secretion of endogenous adrenocortical 

 steroids. They also have been produced by alarming stimuli, which increase 

 the secretion of endogenous ACTH and in turn endogenous corticoids. 

 Among these stimuli are cold, emotional trauma, physical trauma, toxic 

 agents, and many others, although the general response to these stimuli is 

 not necessarily quantitatively, or even quantitatively, similar in every case. 



