DEFENSE OF CELLS AGAIXST THEIR AUTOLYTIC EX/AMES 89 



to a minimum, since during life the tissue fluids, and presumably the 

 cell contents, are preponderatingly alkaline. Perhaps a better ex- 

 planation of the attack of the cells by their own enzymes after death 

 is to be sought in the conditions of chemical equilibrium. During life 

 constant new supplies of protein are being brought to the cell, and at 

 the same time the products of proteolysis are presumably being car- 

 ried away by the circulation or being changed by oxidative processes. 

 When circulation stops, the processes of splitting go on without the 

 introduction of new supplies of material, and hence the tissues are 

 not replaced as fast as they are destroj'ed, and the products of their 

 decomposition accumulate, for lack of any means of destroying or re- 

 moving them. The control of autolysis by maintenance of a low 

 H-ion concentration is, however, undoubtedly an important factor, 

 for Bradley ^ found that a reaction equal to that of blood almost com- 

 pletely inhibits autolysis, while the degree of increased H-ion con- 

 centration that may develop in local asphyxia, or after death, produces 

 optimum conditions for autolj^sis. 



Still another possible defense of the living cells may be found in 

 the existence of specific antienzymes. Just as the serum contains anti- 

 trypsin, so it seems to contain substances antagonistic to the autolytic 

 enzjones. Levene and Stookey found that tissue juices show a resist- 

 ance to digestion, and Opie found that the serum of inflammatory 

 exudates retarded the action of the autolytic enzymes that are con- 

 tained within the leucocytes. Serum also inhibits autolysis of the 

 tissues, so it is probable that continuance of the circulation may pro- 

 vide antibodies to the tissues to hold the intracellular enzymes in 

 check, possibly without interfering with their action on other pro- 

 teins than those of the cell structure.*^* (See Antienzymes.) Lack 

 of oxygen cannot be held solely responsible, according to the studies 

 of Morse,*^'' wdio found that autolysis occurs in muscles with divided 

 nerves but intact blood supply. Nevertheless, reduced blood supply 

 results in increased H-ion concentration which greatly facilitates auto- 

 lysis, and it cannot he denied that autolysis is observed chiefly if not 

 solely in asphyxiated tissues. 



There can be no question that the supply of food-stuff is of essential 

 importance in determining autolytic changes, for it has been found 

 by Conradi,-*^ Rettger.^" and Effront ^'*' that bacteria and yeasts begin 

 to undergo autolysis when they are placed in distilled water or salt 

 solution, which they do not do, to an}- such extent at least, when in 



47a According to Gusrgenheimer (Deut. Arch. klin. Med., 1013 {112). 248: Dent, 

 med. Woch., 1914 (40), 63), the serum in various diseases has a characteristic 

 stimulating or inhibiting effect on in vitro tissue autolysis, hut the conditions of 

 such experiments are so complex as to make their significance doubtful. 



47b Amer. Jour. Phvsiol.. 101.5 (3fi). 147. 



48 Deut. med. Woch., 1003 (20). 26. 



49 , Jour. Med. Research. 1004 (13). 70. 



50 Bull. Soc. Chim., 1005 (33), 847. 



