272 THE BIOCHEMISTRY OF B VITAMINS 



Perhaps of the most striking interest in recent years has been the 

 study of B vitamin requirements in severe injury. Most of such studies 

 have shown, however, only that increased vitamin intakes produce some 

 type of beneficial result. Thus, Govier and Greer 39 found that in dogs 

 with hemorrhage-induced shock, although all eventually succumbed, the 

 average survival time of thiamine-treated controls was 2.4 times that 

 of an untreated group. They found that the elevated pyruvic acid (4.5 

 mg per cent),* blood sugar and blood lactic acid levels occurring in 

 shock were all returned to normal by thiamine administration. Moreover, 

 a high plasma thiamine level seems to add to the resistance to the onset 

 of shock. 40 Finally, cocarboxylase is dephosphorylated in shock, but is 

 apparently resynthesized as a result of thiamine administration. 41, 42 In 

 these cases, as Govier points out, a thiamine deficiency in a sense may 

 exist even though there is an ample thiamine supply, since the thiamine 

 is converted to a metabolically useless form. Greig 43 has shown that this 

 same situation prevails in anoxia, and that similar breakdowns of co- 

 enzyme I and flavin adenine dinucleotide may occur in these cases. Thus, 

 the requirements under such acute pathological conditions are obviously 

 considerably elevated at least for thiamine, riboflavin and niocin. 



These observations have been confirmed to some extent in humans. 

 Andreae, Schenker and Browne 43 studied riboflavin excretion in 23 cases 

 of burns and injuries. Among healthy controls about one-half of a 5-mg 

 oral dose of riboflavin was retained, whereas patients with acute injuries 

 showed a much higher retention for 3 to 5 days immediately following 

 the injury. Subsequently there was abnormally high riboflavin excretion, 

 followed by a return to normal at about ten days following the injury. 

 One might suppose that the vitamin retained during the first period (or 

 that formed from the coenzyme decomposition) was not further used, 

 but stored in some unusual manner for a period and then excreted. Leven- 

 son et al. 45 studied six patients with severe, acute surgical conditions and 

 found similar abnormalities in thiamine, riboflavin and nicotinic acid 

 metabolism. All this work seems to accord well with the known facts 

 regarding coenzyme breakdown 46 (p. 352) . 



There has been a variety of reports regarding the effects of gastro- 

 intestinal disturbances and surgery upon B vitamin requirements. In a 

 typical case, signs of pellagra were observed some four weeks after 

 stomach resection. These disappeared on thiamine and nicotinic acid 

 therapy. In another case, polyneuritis attendant upon adhesions of the 

 omentum was cured by relaparotomy followed by thiamine therapy. 47 

 Little definite information is available regarding the basis for such effects. 



The effects of endemic disease on the B vitamin requirements are vir- 



* Normal, 1-2 mg per cent. 



