292 HORMONES 



growth of a beard, atrophy of the breasts, cessation of menstruation, and 

 development of a mascuhne-type musculature. 



In the last few years several of the most common and distressing human 

 diseases of previously unknown origin have been found to respond to 

 treatment with adrenal hormones. The outstanding example is rheuma- 

 toid arthritis, a painful crippling disease characterized by swelling and 

 inflammation of the joints. Arthritic patients had sometimes been ob- 

 served to show improvement under stress (late pregnancy, starvation, 

 major surgery, etc.). Since it was known that adrenal function also is 

 increased by stress, Hensch and Kendall reasoned that some of the adrenal 

 hormones might be of value in arthritis. Their report describing the 

 beneficial effect of cortisone and ACTH appeared in April 1949 and was 

 quickly followed by confirmatory findings elsewhere. 



Great efforts have been made by chemical and pharmaceutical firms 

 to produce these substances in adequate amounts. Cortisone has been 

 obtained synthetically by an involved process starting with cholic acid 

 from cattle bile (p. 96). Recently, certain plant steroids have been 

 found which can be used as starting materials and greatly simplify the 

 synthetic process. As a result, prices have been reduced and supplies 

 increased, although larger amounts are still needed. ACTH, on the other 

 hand, has not been synthesized and can only be obtained from animal 

 pituitary glands. This is a limited and costly source. Investigations 

 of the structure suggest that only part of the ACTH protein is needed 

 for the biological effect and that the activity may, in fact, reside in a 

 rather small peptide portion of the molecule. If the exact structure of 

 this peptide can be established, there will be a possibility of producing 

 it synthetically in any desired amount. 



Sex hormones 



This term is applied to hormones secreted by the gonads (ovaries and 

 testes), although several other glands are equally essential for reproduc- 

 tion. Whether or not the adrenals normally produce sex hormones is 

 uncertain, although the effect from abnormal production is well known 

 (see above). 



Functions. The periodic sexual cycles of female mammals are con- 

 trolled largely by the ovarian hormones, estradiol and progesterone. 

 These substances are made in the ovary as a result of stimulation by 

 two gonadotropic hormones from the pituitary, namely the follicle-stimu- 

 lating, or follicle-ripening (FSH), and luteinizing (LH) hormones. 

 Figure 11-1 shows how these substances function during a normal human 

 menstrual cycle. 



On the first day of the cycle (first day of menstruation) secretion of 

 FSH begins and causes one of the primitive, undeveloped egg sacs, or 



