RELATION OF AUTOrAHfS TO M F.TMiOIJSM 87 



(I.aqm'ur). Thoro is disagrooiiient as to vvlietlier radium rays auf,'ment autolysis. •■'•■* 

 Injection of iodids into animals is said to increase the jjostinortem autolysis of 

 their tissues (Stookey, Kepinow), as also do iron salts,3:ib while lar>re doses of 

 salicylates decrease it (Laciucur). ]Morse ''■*f attributes the acceleratinj; action 

 of iodin and Itromin to increased acidity from formation of halogen acids, and 

 Bradley " finds evidence that most inorganic salts that stimulate autolysis act 

 by increasing Il-ion concentration. Addition of tuberculin to tissues at first 

 delays and tiien increases the autolysis ( Pe.sci ;^» ) . and dii)htheria toxin in snuiU 

 amounts increases autolysis ( Barlocco,-*'' Bertolini 3<i ) , neutralization by anti- 

 toxin not preventing this effect. Lipoids also accelerate autolysis (Satta and 

 Fasiani37). According to Soula ^'a narcotic poisons decrease, and convulsive 

 poisons increase the rate of autolysis of nervous tissue. Glucose in one per cent, 

 concentration decreases autolysis, and this may be related to the "protein-sparing 

 action of carboliydrates." 3Tb Extracts of various ductless glands, or removal of 

 tliese glands from animals, seem to liave but slight effect on autolysis. •'!■<■ 



RELATION OF AUTOLYSIS TO METABOLISM 

 It liavino- been shown that proteases are present in all cells, the next 

 question to be considered is, do they act only to destroy tissues after 

 death, or are they of importance in metabolism? Since it is pre- 

 sumably necessary for proteins to be split into diffusible and easily 

 oxidized forms in order that they may enter the cell, and be built up 

 into the cell proteins, or be decomposed with the liberation of energy, 

 the autolj^tic proteases may be assumed to be of prime importance in 

 protein metabolism ; but to prove it is another matter. Jacoby found 

 that if he lig-ated off a portion of the liver and let it remain in situ 

 in the animal the necrotic tissues showed an accumulation of leucine, 

 tyrosine, and other splitting products of the proteins, which suggested 

 that these same bodies are being formed in the liver constantly, but 

 that they are as constantly removed from the normal organs by the 

 circulating blood, or are undergoing further alterations which cease 

 when the circulation is checked. The influence of various chemicals 

 upon nitrogen elimination seems to correspond to their effect on 

 autolysis (Izar,^^ Laqueitr^^). Also, the histological changes of star- 

 vation are similar in many respects to those of autolysis (Casa- 

 Bianchi"*°). Among other observations possibly bearing on the same 

 question are those of Hildebrandt," who found that autolysis in the 



33 See Loewenthal and Edelstein, Biochem. Zeit., 1008 (14), 48o : Brown \rch 

 Int. Med.. 1912 (10), 405. 



33bKottmann. Zeit. exp. Path., 1912 (11), 355. 

 330 .Tour. Biol. Chem., 1915 (22), 125. 



34 Cent. f. Bakt., 1911 (59), 71 and 186. 



35 Cent. f. Bakt., 1911 (60), 43. 



36 Biochem. Zeit., 191.3 (48), 448. 



37 Berl. klin. Woch.. 1910 (47), 1500. 



37a Conipt. Bend. Soc. Biol., 1913 (73). 297. 

 37b Shaffer. Proc. Soc. Biol. Chem., 1915 (81. xlii. . 

 37c Izar and Faciuoli, Sperimentale. 1916 (70). 265. 

 3" Internat. Beitr. Erniihrmigstor., 1910 (1), 287. 

 30 Zeit. physiol. Chem.. 1912 (79). 1 pt seq. 



40 Frankfurter Zeit. Pathol.. 1909 (3), 723. 



41 Hofmeister's Beitr-ige, 1904 (5), 463: see also Grimmer, Biochem. Zeit., 1913 

 (53), 429. 



