MKCIIAMSM OF IIKMOI.YSIS 211 



Hemolysis by Known Chemic\l and Physical Agencies 



The Mechanism of Hemolysis — -If distilled water is added to 

 corpuscles of any kind, osmotic changes arc l)ound to occur, since 

 within tlic cells arc abundant salts, soluble in water, whicii will begin 

 to diffuse outward in an attempt to establish osmotic equilibrium be- 

 tween 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 hemo- 

 globin to escape and enter the surrounding fluid. Before this oc- 

 curs 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 hemo- 

 globin 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 inj\ny 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 occurs. As hemoglobin is per- 

 fectly soluble in salt solution, it should pass out if it diffused as do the 

 salts. Since there is no escape of hemoglobin in such a salt solution, 

 it is evident either that the stroma is not permeable to hemoglobin, or 

 else the hemoglobin is in some way attached to or combined with 

 the stroma. Again, if the corpuscles are placed in a solution of salt 

 more concentrated than their own fluids, water escapes and the cor- 

 puscles shrink; as no hemoglobin escapes with the water, it is evident 

 that the stroma is not permeable to hemoglobin when intact. Because 

 of the resemblance of the process of hemolysis to the rupture of plant 

 cells with escape of their contents when they are placed in distilled 

 water, it might be assumed that hemolysis is largely a phj'sical matter, 

 but if a red corpuscle in an isotonic solution is cut into pieces, the 

 hemoglobin does not escape, indicating that its structure is quite 

 dissimilar to that of the simple vegetable cell and that there is some 

 union of stroma and of hemoglobin, either physical or chemical.-^ 

 Physico-chemical studies also indicate that there is no true covering 

 membrane to red corpuscles, for the absorption of ions by hemoglobin 

 is the same as the absorption by corpuscles.-^ M. H. Fischer'"^ 

 interprets hemolysis as a separation of lipoid-protein stroma and ad- 



28 Stewart (Jour, of Physiol, 1899 (24), 211) found that in hemolysis by 

 physical means or under the influence of serums, there is no marked increase in 

 the electrical conductivity, but hemolysis by saponin and by water causes an 

 increase of conductivity, presumably because of the escape of electrol^'tes ; cor- 

 roborated by A. Woelfel, Biochem. Jour., 1908 (3), 146; see also Moore and Roaf, 



tuid D S ^ 



" Rohonyi, Kolloid-chem. Beihefte, 1916 (8), J37, 391. Knaffel-Lenz (Arch, 

 ges. Physiol., 1918 (171), 51) also finds evidence that there is no limiting lipoid 

 membrane about red cells. 



30 Kolloid Zeit., 1909 (5), 146. 



