418 VIII. CHOLESTEROL AND RELATED STEROLS 



results were reported by Schonheimer and Hrdina^^^ in the case of blind 

 loops of the small intestine. According to these latter investigators, a 

 similar situation had been observed in 1911 by Boehm."^ In the case of a 

 woman patient, several grams of ;5-cholestanol had accumulated in a loop 

 of the intestine following a surgical accident. These results prove con- 

 clusively that ;5-cholestanol is formed in the tissues, and is excreted by way 

 of the intestinal wall. In common with phytosterols and ergosterol, ad- 

 ministered cholestanol has been reported to inhibit cholesterol absorption 

 from the small intestine of cockerels, ^^ of rats,^^ and of mice.^^ 



(4) Steroid Hormones 



There can be no doubt that the several steroid hormones are derived di- 

 rectly or indirectly from cholesterol. These compounds represent a group 

 of steroids from which the aliphatic chain at carbon 17 has been largely or 

 completely removed ; the main series of such hormones have either seven- 

 teen, nineteen, or twenty-one carbon atoms. They are all fat-soluble 

 compounds which, however, may be excreted in the urine after conjugation 

 with glucuronic or sulfuric acid. Small differences in composition produce 

 marked alterations in physiologic properties. There will be no attempt in 

 this volume to review the intermediary metabolism of these compounds, 

 as they constitute a separate category of knowledge which is not too well 

 defined. For a further discussion of this subject the reader is referred to 

 the excellent treatises of Dorfman and Ungar,"^^- Schwenk,^'^^ Dorfman,^^^ 

 Dobriner and Lieberman,"^ Zander,"^ and Heard, ^" and also to volumes 

 I, II, and VII of the Ciba Foundation Colloquia on Endocrinology, which 

 deal with these hormones and adrenocortical steroids."** 



"1 R. Boehm, Biochem. Z., S3, 474-479 (1911). 



^^^ R. I. Dorfman and F. Ungar, Metabolism of Steroid Hormones, Burgess, Minneapo- 

 lis, 1953. 



*'^ E. Schwenk, Synthesis of the Steroid Hormones, in F. R. Moiilton, The Chemistry 

 and Physiology of Hormones, Am. Assoc. Advancement Sci., Washington, D. C, 1944, 

 pp. 129-143. 



^^* R. I. Dorfman, Biochemistry of Androgens, in G. Pincus and H. V. Thimann, The 

 Hormones, vol. I, Academic Press, New York, 1948, pp. 467-548 {Metabolism, pp. 517- 

 534). 



"^ K. Dobriner and S. Lieberman, The Metabolism of Steroid Hormones in Humans, in 

 E. S. Gordon, A Symposium on Steroid Hormones, Univ. Wisconsin Press, 1950, pp. 46-88. 



"« J. Zander, Klin. Wochschr., SO, 873-882 (1952). 



^'^ R. D. H. Heard, Chemistry and Metabolism of the Adrenal Cortical Hormones, in 

 G. Pincus and K. V. Thimann, The Hormones, vol. I, Academic Press, New York, pp. 

 549-629. 



^^* Ciba Foundation Colloquia on Endocrinology, vol. I, Steroid Hormones and Tumor 

 Growth, and Steroid Hormones and Enzymes; vol. II, Steroid Metabolism and Estimation, 

 Blakiston, Philadelphia, 1952; vol. VII, Synthesis and Metabolism of Adrenocortical 

 Steroids, Little, Brown, Boston, 1953. 



