424 THE BIOCHEMISTRY OF B VITAMINS 



Deficient pigs show poor growth and become emaciated, develop a 

 rough, dry coat, and later lose their hair, have a prominent gastro- 

 enteritis, and an uncoordinated gait, described as goose-stepping with 

 the hind legs. 167 - 168 



Pantothenic acid is now known to function as part of coenzyme A in 

 acetylation processes. These processes are at present believed to include 

 the acetylation of choline and aromatic amines, and the condensation of 

 oxalacetate to form cis-aconitate, although they may be much more 

 extensive (p. 195). While a large number of facts of biochemical interest 

 are known concerning pantothenic acid deficiency, these do not as yet 

 fit neatly together to provide a clear-cut explanation of the "biochemical 

 lesions" that occur in this condition. An almost certain factor, however, 

 lies in the adrenal atrophy that is so pronounced in rats, since many of 

 the symptoms of the avitaminosis are characteristic of adrenal pathology. 

 While the biogenesis of the adrenocortical hormones is unknown, it is at 

 least tempting to suggest that it proceeds through an acetylation at the 

 17 position which may be pantothenate-mediated, followed by oxidation 

 of the 21 -methyl group, in somewhat the following manner: 



J + CH 3 CO~ C ° enZyme -^> 

 CH, 



ho 



[0] 



CH 2 OH 



progesterone-like I 



intermediate 9^ 



desoxycorticosterone, etc. 



In this manner failure of the acetylation process might well result in 

 adrenal insufficiency. Desoxycorticosterone itself is not effective in treat- 

 ing the hair graying in deficient animals, but other closely related keto- 

 steroids are well known for their efficacy in restoring hair pigmentation 

 in man under many other conditions. It has been shown, moreover, that 

 deficient animals do actually have an adrenal cortical insufficiency, which 

 produces such sequelae as the loss of abdominal fat, decreased testicular 

 function, deranged water metabolism and reduced growth. 169-171 



