764 VII. LIPID DISTRIBUTION IN SPECIFIC TISSUES 



and then decreased to less than 56% twelve days after the operation. Thus 

 the amount of cerebrosides present during degeneration changed in a man- 

 ner opposite to that occurring during the growth of the nerve. 



May 328 noted that normal dry nerve contained 7.8% of cholesterol. 

 During the three weeks following section of the nerve, the cholesterol 

 content increased to 24%. However, measured on a wet basis, an actual 

 decrease in cholesterol obtained. Randall 324 reported that the peripheral 

 nerves from diabetic and arteriosclerotic patients exhibited a marked de- 

 crease in phospholipids, cholesterol, and cerebrosides, and an increase in 

 fat content, but no change in the proportion of water, when compared 

 with corresponding nerves from normal individuals. The posterior tibial 

 nerve displayed the most extensive change in composition as compared 

 with the normal, followed in order by the sciatic and the femoral nerves. . 



The concentration of phospholipids in the peripheral nerves of the rat 

 was found to be a function of the weight of the animal rather than of the 

 age. Thus, Mannell 329 observed that the mean concentration of phos- 

 pholipids in the nerves of protein-depleted rats was greater than in controls 

 of the same age, but did not differ significantly from that of controls of the 

 same weight. 



(5) The Lipid Composition of the Nerve Structures 

 of Invertebrates 



In general, the same type of lipids makes up the nervous tissue of in- 

 vertebrates as has been shown to exist in that of the higher animals. 



Table 18 



The Lipid Composition (in per Cent Moist Weight) of the Nerve Tissue of Some 



Invertebrates 



Esophageal ring Ventral nerve cord 



Substance present Loligo" Limulusb Limulusb Libiniab 



Total phosphatide 3.21 1.36 0.99 0.75 



Lecithin 1.17 0.61 0.42 0.34 



Monoaminophospholipid 2.81 0.84 0.56 0.52 



Total cholesterol 0.73 0.28 0.21 0.16 



Free cholesterol 0.72 0.26 0.20 0.14 



Cerebroside 0.03 0.07 0.09 0.64 



a J. D. McColl and R. J. Rossiter, J. Exptl. Biol, 28, 116-124 (1951). 



b J. D. McColl and R. J. Rossiter, /. Cellular Comp. Physiol, 36, 241-250 (1950). 



328 R. M. May, Bull soc. chim. biol, 30, 562-566 (1948). 



329 W. A. Mannell, Federation Proc, 12, 242 (1953). 



