PHYSIOLOGY, PHARMACOLOGY, AND TOXICOLOGY 381 



part be prevented or cured by B vitamin, liver or yeast administra- 

 tion. 2, 3 - 115 The thiamine content of rat tissues decreases when the animal 

 is rendered hyperthyroid, and there is increased thiamine excretion. 4, 5 

 Thiamine administration in some cases of Graves' disease has been shown 

 to be beneficial, and it seems apparent that many of the symptoms of 

 hyperthyroidism are due to the conditioned malnutrition caused by in- 

 creased vitamin requirements. There is known to be a real possibility that 

 the thyroid and other glands have a marked influence on vitamin metab- 

 olism, particularly at points involving absorption and excretion, but the 

 nature of such effects is at present too obscure to permit any detailed 

 consideration. The involvement of the so-called "digestive hormones" in 

 this regard would seem to be of special interest, but has been little 

 studied. 



Adrenal Cortical Relationships. Pantothenic acid-deficient animals 

 develop a characteristic lesion of the adrenal cortex, 6 and adrenalectomy 

 in such animals prevents the typical gray hair syndrome, 7 although 

 desoxycorticosterone administration permits hair graying to occur. 8 This 

 relationship has been extensively studied, and is discussed in greater 

 detail in the next chapter. Despite the fact that there is still considerable 

 disagreement as to whether apantothenosis produces adrenal hypofunc- 

 tion or hyperfunction, it is at least clear that there is involved here an 

 intimate relationship between pantothenic acid, desoxycorticosterone, and 

 melanin formation, and that this bids fair to be the first direct vitamin- 

 hormone interrelationship to be understood in any detail. Many of the 

 other symptoms of pantothenic acid deficiency, such as the deranged 

 water and salt balance, are undoubtedly manifest through adrenal mal- 

 function. 9 - 12 



Interrelationships with the Gonads and Reproduction. Whereas cer- 

 tain of the fat-soluble vitamins have been linked with sexual and repro- 

 ductive functions by tradition, there is no fundamental reason to attribute 

 such a role to them and not the B vitamins. B Vitamin deficiency most 

 certainly results in sterility, and this point will be mentioned again later. 

 There are rather specific manners, however, in which the androgenic and 

 estrogenic substances are related to the B vitamins, and these are con- 

 sidered here. 



Certain steroid hormones, largely androgenic in nature, have now been 

 found to have an important role in nitrogen, inorganic phosphorus, and 

 potassium retention, in castrate animals, eunuchs, and normal animals 

 including man. 13 The administration of testosterone, for instance, pro- 

 duces an abrupt drop in urea excretion but also a hypoproteinemia, and 

 it is felt that nitrogen retention is involved with the laying down of 

 tissue protein. Whether nitrogen retention is a cause or result of this 



