366 



Profs. J. G. Adami and L. Aschoff. 



[June 6, 



examining when cool, there were now abundant anisotropous globules, with 

 typical black crosses and alternating bright quarters. These occurred more 

 particularly in the neighbourhood of and lying over the cholesterin plates, which 

 showed some signs of erosion. The indications pointed to the conclusion that 

 here cholesterin had been taken up by the fatty globules which then became 

 anisotropic* We have repeatedly noted that after warming specimens — 

 smears — from the atheromatous aorta, the spherocrystals which had been 

 •colourless became prismatic, and this prismatic colouring is characteristic of 

 cholesterin compounds. Virchow's observation, confirmed by Beneke, regarding 

 the existence of " myelin " in the gall bladder is significant, and when to this 

 we add Hiirthle's demonstration that cholesteryl oleate is a constant 

 constituent of the blood, and that of Aschoff that fat is absorbed actively by 

 the epithelium of the gall bladder, thus affording the most satisfactory 

 explanation yet given of the development of cholesterin calculi — cholesteryi 

 •oleate being excreted and becoming dissociated — we gain strong ground for 

 believing that cholesteryl oleate is a more important factor in myelin formation 

 than has hitherto been held. If we cannot accept in its entirety Beneke's 

 dictum " ohne Cholestearin keine Myelinformen," we recognise that his view, 

 so long discredited, gains a measure of support, at least for some instances of 

 myelin formation. 



The case in favour of cholin oleate is more novel. So far as we are aware, 

 this substance has not hitherto been isolated. Liebreich, in 1865, came 

 close to making the discovery, but was misled by his prepossession in favour 

 of protagon, which he was the first to isolate. He then showed that (1) 

 protagon alone does not produce myelin forms, (2) protagon with oleic acid 

 (with which it readily mixes) also gives negative results, (3) a trace of 

 neurin (cholin) added to the above mixture results in the production of 

 exquisite myelin figures. And he concluded that bodies, like protagon, which 

 have the power of swelling in water and of being dissolved in fatty acids, 

 develop myelin forms when dissolved in the respective soaps of these acids. 

 The neurin, he pointed out, must here form a soap with the excess of fatty 

 acid, just as did Na, K, or NH 3 , which gave the same myelin formation. The 

 fourth experiment, to complete the series, he never attempted. Had he done 

 so he would have found that the presence of protagon is not essential, that 

 cholin combines with oleic acid in the cold, forming immediately a thick 

 crystalline fluid, a drop of which placed in water forms most extraordinary 



* As confirming Klotz's observations upon the differential staining of neutral fats and 

 soaps with Sudan III, it may be noted that in another atheromatous aorta we found that 

 the globules which were doubly refractive assumed a paler stain with this dye, the fatty 

 isotropous globules a deeper red. 



