QUANTITATIVE RELATIONS OF BLOOD LIPIDS 385 



sterol reached an equipartition in cells and plasma within four hours; 

 actually a 50% equilibration obtained within one hour. On the other 

 hand, esterified cholesterol did not participate in the interchange. These 

 workers believe that it is unlikely that the entire lipoprotein molecules 

 interchange, inasmuch as plasma lipoproteins were found to contain both 

 free and esterified cholesterol, while the red blood cells contained only the 

 free form. 



Table 7 



Distribution of Cholesterol, Cholesterol Esters and Phospholipid Phosphorus 



in the Plasma and Blood Cells of Man" 



Category Plasma, mg. % Cells, mg. % 



Cholesterol 



Total 192.7 ± 35.5 173.0 ± 27.6 



Esters 129.3 ± 25.0 15.3 ± 20.3 



Phospholipid P. 9.0 ± 1.2 14.1 ± 1.4 



a F. F. Foldes and A. J. Murphy, Proc. Soc. Exptl. Biol. Med., 62, 215-218 (1946). 



Changes in the levels in cell lipids occur much less readily than do varia- 

 tions in the plasma lipids. They are not affected appreciably by diet or 

 by a variety of physiological factors. According to Peters and Van Slyke, 202 

 one may completely miss important variations of the lipid phosphorus or of 

 free cholesterol in plasma if analyses are made on whole blood. This is 

 attributable to the fact that the cells contain much larger proportions of 

 the aforementioned components, and will thereby mask slight changes in 

 these fractions in the plasma. 



Globoside is a glycolipid which has been isolated from the stroma of the 

 red blood cells of human blood, as well as from those of the sheep, goat, and 

 hog, by Yamakawa and Suzuki. 203 Since it contains hexosamine (or chon- 

 drosamine) but no hemataminic acid, this type of glycolipid is classified as a 

 globoside rather than as a hematoside. On the other hand, Yamakawa 

 and Suzuki 203 note that the stroma lipid isolated from the dog and the horse 

 have hemataminic acid and very little hexosamine. Bovine stroma pos- 

 sesses both components, while neither type was found in chicken stroma. 



Klenk and Lauenstein 204 reported the composition of the erythrocyte 

 stroma of man and ox as follows: fatty acids (mainly lignoceric), 25%; 

 sphingosine, 16%; sugar (galactose, glucose, glucosamine), 56 to 57%. 



202 J. P. Peters and D. D. Van Slyke, Quantitative Clinical Chemistry, Vol. I, Interpreta- 

 tions, 2nd ed., Williams & Wilkins, Baltimore, 1946. 



203 T. Yamakawa and S. Suzuki, J. Biochem. (Japan), 38, 199-212 (1951); 39, 393-402 

 (1952); 40, 7-10(1953). 



204 E. Klenk and K. Lauenstein, Z. physiol. Chem., 291, 249-258 (1953). 



