FACTORS AFFECTING RATE OF ABSORPTION 191 



Barnes, Rusoff and Burr 858 later reported that emulsified hydrogenated 

 cottonseed oil did show a decreased absorption rate in adrenalectomized 

 rats, but that no deviation from the normal could be noted in the absorp- 

 tion of corn, olive, hydrogenated cottonseed oil, or mutton tallow which 

 could be related to ablation of the adrenals. Bavetta and Deuel 686 were 

 also unable to confirm this later work of Barnes et aZ., 8f,s and suggested that 

 the failure of the latter workers to note differences in their operated rats 

 may have been due to the fact that large (and probably old) rats were used ; 

 it is well known that cortical deficiency is much more critical in younger 

 animals. 



In spite of the fact that the adrenocortical hormones are essential for the 

 efficient absorption of the common fats, apparently they do not function in 

 a similar manner in the case of triglycerides having water-soluble fatty 

 acid components. Thus, Bavetta and Deuel 686 noted that the rate of ab- 

 sorption of tributyrin was not influenced by adrenalectomy. Bavetta 687 

 later found that the same was true in the case of triglycerides containing 

 other water-soluble acids, as well as of the acids themselves when given as 

 their sodium salts. 



{5) The Effect of Inhibitors on Fat Absorption 



Substances such as monoiodoacetic acid and phlorhizin, which pre- 

 sumably inhibit phosphorylation, have been shown to decrease the rate of 

 absorption of fat or of fatty acid in rats. 



a. Monoiodoacetic Acid. Although there seems to be little question 

 that iodoacetate interferes with the absorption of glucose, galactose, and 

 fructose, but not of the pentoses, xylose, and arabinose, 859 it appears to be 

 questionable whether a similar interference obtains in fat absorption. 

 Verzar and McDougall 554 report experiments on rats given 3.5 ml. of olive 

 oil without (.4) or with (B) monoiodoacetic acid in a dosage of 0.07 to 0.1 

 mg. per g. body weight. After six hours, the following comparative results 

 were obtained: fat absorbed, .4, 1 to 1.4 g., B, g.; fat in stomach A, 

 1.5 g., B, 3 g. ; fat in intestine, A, 0.5 g., B, 0.5 g. Failure in absorption 

 is not due to the fact that fat largely remained in the stomach in the iodo- 

 acetate-injected rats, as is shown by the inability of such animals to ab- 

 sorb the fat when it is introduced directly into the intestine. Moreover, 

 monoiodoacetic acid was shown to have no inhibitory action on lipase. 860 



858 R. H. Barnes, I. I. Rusoff, and G. O. Burr, Proc. Soc. Exptl. Biol. Med., 49, 84-87 

 (1942). 



859 w. Wilbrandt and L. Laszt, Biochem. Z., 259, 398-417 (1933). 



860 F. Barth. Biochem. Z., 270, 63-65 (1934). 



