CYTOLYSINS 139 



Hemolysis may be caused by other physical agents, such as 

 freezing (particularly when followed by thawing), heat of 62 to 64 C. 

 in the case of mammalian corpuscles or slightly less in the case of 

 cold-blooded animals and, as Rous has shown, by shaking. 



Chemical Hemolysis. The influence of chemicals on hemolysis 

 appears to be a factor of their permeation of the stroma. Wells states 

 that there seem to be two types of permeating substances, one such as 

 urea, which does not act in isotonic solutions of sodium chloride, and 

 the other such as ammonium chloride, which acts either in isotonic or 

 non-isotonic solutions. Hamburger, as quoted by Wells, states that 

 erythrocytes in relation to organic substances are (a) impermeable 

 for sugars, including cane sugar, dextrose, lactose, arabinose and man- 

 nose; (b) permeable for alcohols in inverse proportion to the number 

 of hydroxyl groups they contain, also for aldehydes (except paralde- 

 hyde), ketones, ethers, esters, antipyrin, amides, urea, urethan, bile 

 acids and their salts; (c) slightly permeable for neutral amino-acids, 

 such as glycocoll and asparagin. In relation to inorganic substances, not 

 including the salts of fixed alkalis, the erythrocytes are (a) " imperme- 

 able for the cations Ca, Sr, Ba, Mg, and (b) permeable for NH 4 ions, 

 for free acids and alkalis." It will be noted that certain of the organic 

 substances for which the cells are permeable are solvents of lipoids, 

 particularly those lipoids of the stroma, cholesterol and lecithin, a 

 phenomenon which will be referred to again in discussing venom 

 hemolysis. Other chemical hemolysins include veratrin, digitalin, 

 arseniuretted hydrogen (in the body but not in the test tube), nitro- 

 benzol (important in denatured alcohol poisoning), nitrites, guaiacol, 

 pyrogallol, aniline compounds, alcoholic extracts of tissues and products 

 of tissue autolysis. Salt solution extracts of various organs are 

 hemolytic and have been called organ hemolysins. These bodies 

 resist boiling, do not act as antigens, hemolyze at 37 but not at o C., 

 are not increased in activity by complement but are inhibited by the 

 presence of serum. Noguchi has studied alcoholic tissue extracts ex- 

 tensively and finds them also hemolytic. He has come to the con- 

 clusion that the active elements in organ hemolysis are soaps. 



Bacterial Hemolysins. Bacteria may by their growth lead to suf- 

 ficient acid or base formation in the media as to make the latter 

 hemolytic. Of equal importance is the fact that certain bacteria may 

 produce hemolytic bodies not of definitely acid or alkaline character, 

 called bacterial hemotoxins. These substances include for the most 

 part the products of pathogenic organisms, such as tetanolysin, 

 staphylolysin, streptolysin, typholysin, vibriolysin (El Tor strain of 

 cholera) , anthrax-lysin and certain other less important forms. Certain 

 saprophytes also are capable of producing lysins, as for example mega- 

 theriolysin, proteus-lysin and the lysin of bacillus Welchii and others 

 of the gas gangrene group. An important bacterial hemotoxin is that 

 of bacillus pyocyaneus. The exact nature of these substances is not 

 known, but Burckhardt has shown that staphylolysin is dialyzable, 

 thermolabile, ether soluble and does not give protein or biuret reactions. 



