188 HEMOLYSIS AND SERUM CYTOTOXINS 



of which have then been applied to the subject of bacteriolysis. 

 Both on this account, therefore, and because solution of red 

 corpuscles is of itself an important process in many intoxica- 

 tions and diseases, the subject is of great theoretical and practi- 

 cal importance. 



HEMOLYSIS 1 OR ERYTHROCYTOLYSIS 



In hemolysis the essential phenomenon consists in the escape 

 of the hemoglobin from the stroma of the corpuscles into the 

 surrounding fluid. As it is not exactly known in what way 

 the stroma holds the hemoglobin normally, whether purely 

 physically or in part chemically, or whether the stroma consists 

 of a spongioplasm or a sac-like membrane, or both, the ultimate 

 processes that permit the escape of the hemoglobin are not 

 finally solved. However, the agents by which the escape is 

 brought about are well known and extensively studied, and 

 they are found to be of extremely various natures. They may 

 be roughly classified as : (1) known physical and chemical 

 agents ; (2) unknown constituents of blood-serum ; (3) bac- 

 terial products ; (4) certain vegetable poisons ; (5) snake venoms. 



HEMOLYSIS BY KNOWN CHEMICAL AND PHYSICAL AGENCIES 



The Mechanism of Hemolysis. If distilled water is 

 added to corpuscles of any kind, osmotic changes are bound to 

 occur, since within the cells are abundant salts, soluble in water, 

 which will begin to diffuse outward in an attempt to establish 

 osmotic equilibrium between the corpuscles and the surrounding 

 fluid. Conversely, water enters the corpuscles at the same time, 

 and accumulating there leads to swelling until such injury has 

 been produced as permits the hemoglobin to escape and enter 

 the surrounding fluid. Before this occurs the fluid is opaque 

 because of the obstruction to light offered by the red cells, but 

 on the completion of hemolysis the fluid becomes transparent. 

 The stroma now settles to the bottom, while the hemoglobin 

 diffuses into the fluid, making it red, but perfectly transparent. 

 This process has long been known as the " laking " of blood, 

 and is essentially the condition present in all forms of hemolysis. 

 That the hemoglobin escapes only through injury of the stroma 

 and not through simple osmotic diffusion is shown by the fact 

 that if salt solution of the same concentration as normal serum 

 is used instead of distilled water, no such escape of hemoglobin 



1 Through usage this term has been limited to the solution of the red cor- 

 puscles, which is more accurately described by the term erythrocytolysis. For 

 bibliography see Sachs, Ergebnisse der Pathol., 1902 (7), 714. 



