686 VI. OCCURRENCE OF LIPIDS IN THE ANIMAL 



Fat mobilization to the liver produced by anterior pituitary extracts is 

 completely abolished following adrenalectomy. 873 However, Levin and 

 Farber 873 demonstrated that, when adrenalectomized mice were pretreated 

 with cortisone, the response to the pituitary hormone by a mobilization of 

 fat in the liver was equal to that of intact mice, or even greater. On the 

 other hand, cortisone and other cortical steroids were found to be ineffective 

 by themselves in increasing the liver fat in these animals. The loss of liver 

 fat usually occurring after adrenalectomy could be prevented by these cor- 

 tical hormones. Li et al. 87i demonstrated an increase in liver fat in normal 

 male rats which were force-fed a fluid containing carbohydrate, and were 

 given injections of 3 mg. of ACTH (adrenocorticotropic hormone) daily for 

 ten days. 



The pronounced effect of adrenalectomy on liver fat is in line with the 

 alterations in ketosis which result from adrenalectomy (see Volume III) . 



d'. Sex Hormones: In 1942, MacBryde and co-workers 875 reported that 

 the administration of female sex hormones, estrone and estradiol, was fol- 

 lowed by the production of fatty livers in dogs. However, the later evi- 

 dence of Gyorgy and collaborators 876-879 indicated rather that a lipotropic 

 action follows the injection of these hormones. As small an amount as 30 

 ng. per day of estrone was shown to have a lipotropic action when adminis- 

 tered to intact and to castrated female rats fed a diet normally producing 

 fatty livers. Estrone had a synergistic effect on the lipotropic action of 

 methionine. 876 Following ovariectomy, the fat content in the liver was in- 

 creased. 877 Ethinyl estradiol was more active than estradiol benzoate or 

 estrone, and was effective whether or not methionine was given. 878 The 

 lipotropic effect is apparently mediated by an extrahepatic factor, which may 

 be activated through the anterior pituitary gland. 



e'. Thyroid Hormones: It is known that blood cholesterol is increased in 

 thyroid deficiency and is reduced with increasing thyroid activity. Han- 

 dler 880 reported that a thyroid deficiency, produced either by extirpation of 

 the gland or by the administration of thiouracil, results in an increase in liver 



873 L. Levin and R. K. Farber, Proc. Soc. Exptl. Biol. Med., 74, 758-763 (1950). 



874 C. H. Li, D. J. Dingle, H. M. Evans, M. C. Prestruda, and J. E. Nezamis, Proc. 

 Soc. Expll. Biol. Med., 70, 753-756 (1949). 



876 C. M. MacBryde, D. Castrodale, E. B. Helwig, and O. Bierbaum, /. Am. Med. 

 Assoc, 118, 1278-1281 (1942). 



876 P. Gyorgy, C. S. Rose, and R. A. Shipley, Arch. Biochem., 12, 125-133 (1947). 



877 R. A. Shipley, E. B. Chudzik, and P. Gyorgy, Arch. Biochem., 16, 301-307 (1948). 



878 P. Gyorgy, C. S. Rose, and R. A. Shipley, Arch. Biochem., 22, 108-118 (1949). 



879 R. A. Shipley, E. B. Chudzik, P. Gyorgy, and C. S. Rose, Arch. Biochem., 25, 

 309-315 (1950). 



» P. Handler, /. Biol. Chem., 178, 295-303 (1948). 



