98 ENZYMES 



be fonned in aseptic dead tissues, but the slow absorption of such 

 tissues is, however, finally accomplished by the leucocytes acting 

 from the periphery, there beino: little actual autolysis of the dead 

 cells by their own enzymes. Tlie rapidity with which autolytic 

 changes occur in different organs, as indicated by the disappearance 

 of nuclear staining, seems to be about as follows: (1) Liver, kidney 

 ^epithelium of convoluted tubules) ; (2) spleen, ])ancreas; (3) kidney 

 (collecting tubules, straight tubules, glomerules) ; (4) lung (alveolar 

 and bronchial epithelium) ; (5) thyroid; (6) myocardium; (7) volun- 

 tary muscle; (8) skin (epithelium); (9) brain (cortical cells). 

 Stroma cells seem to be attacked chiefly by enzymes from the paren- 

 chynui cells. Of all cellular elements, the endotlielium of the vessels 

 seems to have the greatest resistance to both autolysis and heterolysis. 



The finer structural changes of aseptic autolysis of liver in salt so- 

 lution, have been carefully studied by Launoy,**" who notes a period 

 of relative latency (20 to 2-4 hours at 38°), followed by rapid changes 

 in both cytoplasm and nucleus, associated with the appearance of 

 myelin forms. Dj^son ''^ describes loss of the Altmann's granules in 

 autolyzing cells. Cruickshank ^- states that when aseptic autolysis 

 of tissues kept in a moist chamber is observed microscopically the 

 changes are slower, and there is less solution of the cytoplasm, but in 

 general the results are much the same. No fat could be found by 

 special stains. Fetuses that have undergone aseptic autolysis in the 

 uterus show complete loss of nuclei in 5 to 6 days, a stage correspond- 

 ing to 8 to 15 days autolysis in the moist chamber. In experimental 

 nephritis Simons ^^'^ observed a decreased autdlj-sis of the kidneys. 



Degenerated nervous tissue also undergoes a slow autolysis which, 

 according to Noll,"'* results in the splitting of protagon with libera- 

 tion of lecithin. IMott, Halliburton.-''' Donath, and others have shown 

 that in nerve destruction lecithin is split up with liberation of cho- 

 line (see "Choline"). Koch and Goodson **" found that degenerated 

 nervous tissue is characterized, chemically, by containing a relatively 

 increased amount of nucleo-proteins, with an absolute decrease in 

 s'olid constituents, while the lecithins a)"e greatly altered. 



In caseation autolysis is very slight, as is sliown by the persistence 

 of the caseous material for long periods of time witliout absorption. 

 Presumably the toxin of tuberculosis destroys the autolytic ferments 

 of the cells it kills,"' and as thei-e is little chemotactic influence, leuco- 



00 Ann. Inst. Pasteur, 1009 (2:^). 1. 



91. Tour. Patli. and l?act., HU'J (17), 12; also AsdiolV, Vcrli. d.Mit. Path. 

 Gesellscli, 1014 (17), 100. 



92 .lour. Patli. and Pact., 1011 (10), 1G7. 



92a Piodiom. Zoit., 1014 (67), 483. 



94Zcit. pliysiol. Clieni.. 1800 (27), 390, 



05 General r^^'sum^' in Kr<,'elinissc der Plivaiol., 1004 (4), 24. 



98Amer. Jour. Pliysiol., lOOfi (l.")), 272.' 



07 However, Pesoi "(Pa1ii(d()-ica, 1012 CM. 144) slates tlial liilierculiii increases 

 autolysis in vitro. 



