768 VII. LIPID DISTRIBUTION IN SPECIFIC TISSUES 



immediately after the operation, reached a maximum in sixty days, began 

 to decline after 270 days, and returned to normal after one year. Fatty 

 acids and phosphatides first showed a reduction following extirpation of the 

 spleen, but approximately normal levels were obtained after one year. 

 These data are interpreted as indicating a relationship between the spleen 

 and the suprarenal glands. Marino 350 ' 351 also reported that hemorrhage 

 produced a decrease in cholesterol, along with a rise in other lipids in the 

 adrenal glands. During blood regeneration all lipids increased in this 

 organ. After the administration of hemolytic poisons, cholesterol increased 

 at first, but later diminished to a subnormal value in the suprarenal cap- 

 sule. When blood regeneration was taking place following the hemolysis, 

 the low cholesterol level persisted in the adrenal glands. Adams and Bax- 

 ter 352 reported that the cholesterol and total lipid content of the adrenal 

 glands, as determined in seventy-seven autopsy specimens from individuals 

 who had had hypertension or arteriosclerosis, were not elevated above nor- 

 mal values. 



The reproductive cycle in the rat is without profound effect on the level 

 of the free cholesterol in the adrenal gland. Andersen and Sperry 353 

 reported constant values during this cycle. On the other hand, the level 

 of ester cholesterol was lower in ovariectomized, pregnant, and parturient 

 rats than it was in normal females during estrus, diestrus, or lactation. 

 These workers failed to demonstrate any relationship between the chole- 

 sterol level in the serum and in the adrenal gland. Moreover, Simonnet 

 et al. 354 noted no differences in the cholesterol content of the adrenals from 

 normal and from castrated rats. The cholesterol levels were given as 2.3 

 and 2.4 milligram per cent, respectively. Moreover, castration did not 

 influence the ratio of free to esterified cholesterol. 



Adrenalin, which is produced by the medullary tissue, is believed to 

 control the lipid level in the suprarenal cortex. Thus, Vogt 355 reported 

 that repeated injections of adrenalin over an eight-hour period brought 

 about a decrease in the lipid material in the cortical tissue of the rat and cat. 

 A similar depletion of lipids in the adrenals of rats occurred following the 

 injection of insulin. Since the latter effect could usually be prevented by 

 denervation of the adrenal glands, it is postulated that the loss of cortical 

 lipids following insulin injection in normal animals results from the libera- 

 tion of adrenalin. 



361 S. Marino, Arch, farmacol. sper., 55, 183-206 (1933). 



362 E. Adams and M. Baxter, Arch. Pathol, 48, 13-26 (1949). 



363 D. H. Andersen and W. M. Sperry, J. Physiol, 90, 296-302 (1937). 



364 H. Simonnet, E. Michel, and V. Segal, Compt. rend. soc. tool, 1&, 579-580 (1948). 

 366 M. Vogt, J. Physiol, 106, 394-404 (1947). 



