B VITAMIN DEFICIENCY STATES 431 



of its fat transport functions which involve large amounts of the sub- 

 stance that are not compatible with our present concept of B vitamin 

 activity. One might associate a vitamin function with choline for its role 

 in acetylcholine synthesis, were it not so difficult to extend this to micro- 

 organisms, some of which require a nutritional choline source. Because 

 of the multiplicity of symptoms associated with its deficiency and despite 

 the several possible reasons for these, it is difficult to discuss choline 

 deficiency in the light of an avitaminosis, although it may well be true 

 that choline functions as a vitamin, and that some of the manifestations 

 of its deficiency are due to the breakdown of this function. 



The usual symptoms of choline deficiency are retarded growth, fatty 

 livers with interlobular cirrhosis, renal tubular degeneration, enlarged 

 spleen, and a generalized hemorrhagic condition. 204 - 205 In chicks and 

 turkeys, perosis is also characteristic and egg production subsides. In 

 albino rats normal lactation ceases, and young rats raised from mothers 

 approaching such a state develop a flaccid paralysis of the hind quarters. 

 There is a high nonprotein nitrogen excretion in choline deficiency, and 

 the general indications of impaired renal and hepatic function. Choline 

 is said to depress the polycythemia induced by cobalt 206 and to prevent 

 the necrosis, cirrhosis, and cancer of liver induced by "butter yellow" 

 (dimethylaminoazobenzene) . 207 Neoplasms are frequently formed, more- 

 over, in the livers of choline-deficient rats. 208 There is little in this overall 

 picture to suggest the consequences that result from an impaired function 

 of choline in cellular metabolism, and further studies of choline function 

 in cellular and enzyme systems where fat mobilization and transmethyla- 

 tion effects can be eliminated are needed to elucidate the vitamin role of 

 choline. Choline deficiency has been studied in a variety of other animals, 

 dogs being particularly suitable for such studies. 209 



The Relationship of the B Vitamins to Various "Nondeficient" States. 



A number of pathological conditions are known which, while they bear 

 no apparent relationship to any of the avitaminoses studied, yet respond 

 to B vitamin, liver, or yeast therapy. Whether this is due to insufficient 

 study of the therapeutic effects of the various members of the B group 

 in each case, or the presence of as yet unidentified factors is at present 

 uncertain. Also worthy of consideration are a wide variety of conditions 

 of presumably known etiology which bear no apparent relationship to 

 avitaminoses, but respond favorably to B vitamin therapy. At the present 

 time, when the impetus for study of most of the classical nutritional 

 deficiencies has subsided, the possibilities for spectacular advances in this 

 new field seem unlimited. Only a few suggestions are as yet available, 

 however, to indicate the directions in which such advance may proceed. 



