LIPID STORAGE UNDER ABNORMAL CONDITIONS 667 



planation that hemorrhagic injury of the kidney might result from a de- 

 ficiency of the labile methyl supply. The fact that either betaine or meth- 

 ionine can prevent the kidney degeneration would seem to support such an 

 hypothesis. However, McHenry and Patterson 547 consider that methyl 

 groups are needed merely for the synthesis of choline and not per se for the 

 prevention of hemorrhagic kidneys. They cite as evidence for this con- 

 clusion the fact that triethylcholine 757 and arsenocholine, 758 neither of 

 which contributes to the supply of labile methyl groups, prevent the onset 

 of renal hemorrhage in rats on a low choline diet. However, dimethylgly- 

 cine was ineffective in preventing hemorrhagic kidneys in young rats. 716 

 Monoethyl and diethylcholine chlorides are quite potent as antihemor- 

 rhagic agents, but the tripropyl homologue is inactive. Other active com- 

 pounds include betaine aldehyde chloride and betaine hydrochloride, as well 

 as two sulfur analogues of betaine, namely dimethylthetin hydrochloride 

 ((CH 3 ) 2 SCH 2 COOH(Cl)) and methylethylthetin hydrochloride (CH 3 (C 2 H B )- 

 SCH 2 COOH(Cl)). 759 



The requirement for choline in preventing renal hemorrhagic damage 

 was ascribed by Griffith 750 to the essential character of choline phospho- 

 lipids, since lecithin is an intermediate in fat metabolism and an important 

 component in the cell structure. This viewpoint is strengthened by the 

 report of Patterson and McHenry, 760 and of Patterson el al., 737 that the 

 renal damage which results from a choline-low diet is preceded by a de- 

 creased concentration of phospholipids in both the kidney and the liver. 

 These investigators noted that either choline or triethylcholine maintains 

 the phospholipid within normal limits, and likewise prevents the kidney in- 

 jury. The suggestion is therefore made that the kidney lesions result from 

 an inability of the animal to keep pace with the rapid phospholipid turnover 

 needed to maintain the structure of the growing kidney. Moreover, since 

 the rate of phospholipid turnover is much higher in young rats than in older 

 ones, 761 the possibility of a deficiency at this period of rapid growth is in- 

 tensified. Since all substances which protect the kidney are lipotropic 

 agents, it seems probable that their behavior is traced simply to their stim- 

 ulation of the production of an increased phospholipid supply, with con- 

 sequent improvement in fat transport. A comprehensive review of the 

 antihemorrhagic action of choline-like compounds has been written by 

 Welch. 759 



767 A. D. Welch, J. Biol. Chem., 187, 173-181 (1941). 



788 R. L. Landau and A. D. Welch, Federation Proc, 1, 156-157 (1942). 



769 A. D. Welch, J. Nutrition, 40, 113-131 (1950). 



760 J. M. Patterson and E. W. McHenry, J. Biol. Chem., 145, 207-211 (1942). 



761 G. W. Changus, I. L. Chaikoff, and S. Ruben, /. Biol. Chem., 126, 493-500 (1938). 



