378 V. BLOOD LIPIDS 



administration of testosterone to castrated immature rabbits altered the 

 lipoprotein pattern by resulting in the appearance of two abnormal com- 

 ponents. One of these was an S f > 70 and the second an S f 40 to 70. 

 Both disappeared on the cessation of treatment. The administration of 

 diethylstilbestrol did not bring about a change in the pattern of lipoproteins. 

 Fasoli et al. 177 studied depancreatized dogs under insulin control, and 

 reported that, although both cholesterol and phospholipid levels were higher 

 than normal, the relative proportions of the lipoproteins were not signifi- 

 cantly changed. When insulin was withdrawn, the serum became opales- 

 cent and even milky, due to the increased lipids. There was a sharp in- 

 crease in concentration of low-mobility lipoproteins migrating with the 

 /3-globulins, which is probably to be ascribed to the rapid mobilization of 

 body fat. On the other hand, no consistent change occurred in the high- 

 mobility lipoproteins in untreated depancreatized dogs. 



3. Quantitative Relations of Blood Lipids 



Although the several lipid components in blood vary with diet and species 

 as well as with various physiological and pathological conditions, the fast- 

 ing values are quite constant in different animals of the same type. 



(1) Normal Values of Blood Lipids in Man 



West and Todd 47 cited the values listed in Table 2 as normal for the blood 

 lipids of man. A similar compilation has been made by Boyd, 186 who also 

 calculated the distribution of fatty acids in the plasma of normal women 

 These values are shown in Table 3. 



The distribution of lipids reported by Boyd 186 falls within the average 

 normal range given by West and Todd. 47 The lipid values for man have 

 been shown to be the highest, on an average, of any for the common ani- 

 mals. Bauer and Hirsch 187 reported that the esterified fatty acids in the 

 serum of normal men average 9.2 meq. per liter (7.0 to 12.6). 



a. Unsaturated Fatty Acids in Blood. The unsaturated fatty acid 

 content has been shown to consist principally of oleic acid, with smaller 

 amounts of diene (linoleic) and tetraene (arachidonic). Whereas the 

 amounts of oleic and of linoleic acids were shown to depend in a large meas- 

 ure upon alimentation, linolenic and arachidonic acids are constant con- 

 stituents of the blood under normal conditions. 188 Some normal values for 



186 E. M. Boyd, J. Biol. Chem., 101, 323-336 (1933). 



187 F. C. Bauer, Jr., and E. F. Hirsch, Arch. Biochem., 23, 137-140 (1949). 



188 A. Chevallier, S. Manuel, C. Burg, and J. Rouillard, Compt. rend. soc. biol, 144, 

 577-578 (1950). 



