416 RETROGRESSIVE CHANGES 



tals form <i'listeiiing scales ; in fresh tissues tliey may be recognized by 

 their solubility in ether, chloroform, hot alcohol, etc., and by their 

 color reactions. In histological specimens prepared by the usual 

 methods the cholesterol is dissolved out, but the resulting clear-cut 

 clefts are quite characteristic. In fresh specimens in which choles- 

 terol crj'stals are present, on treatment with five parts concentrated 

 sul])huric acid and one of water, the edges of the crystals become 

 carmine red, then violet. Concentrated sulphuric acid plus a trace 

 of iodin colors the crystals in sequence, violet, blue, green, and red. 

 Hirschsohn '^^ recommends a reaction with a 90 per cent, solution of 

 trichloracetic acid in HCl, which gives red, then violet, then blue. The 

 results of microehemieal examination are said not to agree at all quan- 

 titatively Avith analytic results."^''' 



Since all cells contain cholesterol,''^ it is perhaps accumulated as one 

 of the least soluble products of their disintegration. The origin of 

 the normal cell cholesterol is unknown, but that which is liberated by 

 normal disintegration of cells seems to be retained and worked over." 

 It is not destroyed during autolysis." Cholesterol is generally con- 

 sidered, but without convincing proof, to be a product of protein de- 

 composition ; if this is true, then the cholesterol found in disintegrat- 

 ing tissues may be formed from the cell proteins during their de- 

 composition.'^'* Apparently cholesterol crystals may be slowly re- 

 moved, the chief factor probably being the giant-cells that are often 

 found surrounding them,®° and the large "foamy" endothelial cells 

 that take up especially the uncrystallized cholesterol. In general they 

 behave as inert foreign bodies. Xanthomatous masses of various kinds 

 all seem to be composed of deposits of cholesterol esters which lead to 

 proliferative and phagocytic reactions in the fixed tissues.^*"^ 



Cholesterolemia.**"" — Normal blood contains 1.7 to 2.5 per mille of 

 cholesterol, of which about 55 per cent, is in the corpuscles, both in 

 normal and pathological conditions (Bacmeister and Henes**"^). 

 Cholesterol -rich diet causes a slight increase, but a more marked in- 

 crease is said to be obtained in pregnancy, nephritis, early arterio- 

 sclerosis, obesity, diabetes, and obstructive jaundice. According to 



'SPharm. Contrallialle, in02 (4.3). 357. 



v-.a Thavsen, Cent, allfj. PatlioL, 101.') (2fi), 433. 



TO See boree. Bioeliom. Jour., 1009 (4), 72. 



"Ellis and Cardiier, I'roc. Royal Soc, London. 1012 (S4). 401. 



Ts Corpcr, Jour. Hiol. Cliem., ' 1012 (11), 37: Shiliata, nioclioni. Zoit., 1011 

 (31), 321. 



70 Of historical interest is Austin Flint's idea that clioiesterol in tlie hlood is 

 an important factor in into.xications, especially in icterus (Anier. Jour. Med. 

 Sci., 1862 (44), 20). All recent evidence is tothe etTect that cholesterol is not 

 toxic. 



so See LeCount, .Tour. iNled. Research, 1002 (7), liKl; ('or|)cr, .lour. K\p. ^fcd., 

 101.-) (21). 170: Stewart. .Toin-. Patli. and Ract.. lOlfj (10), 30.'). 



><"" Lit.'rature -riven 1)V Hosenl)looni, Arcli. Int. :\Ied., 1013 (12). 30,-). 



><'>b Pil,li,,trnipliv hv licwcv. Arch. Tut. .Med., 101(5 (17), 7r>7. 



8o<- l)<'iit iiicil. 'W.irh.. l!il';! ( :!".»), r>44. 



