330 RETROGRESSIVE CHANGES 



We may speak with more assurance concerning the swelling 

 of the cell, and attribute it to an increase in the osmotic pres- 

 sure of the cell contents, with consequent taking up of water. 

 The rise in osmotic pressure is probably due to abnormally 

 rapid splitting of proteids with incomplete oxidation of the 

 substances formed, which results in formation of many crystal- 

 loid molecules with high total osmotic pressure, from a smaller 

 number of colloid molecules with almost no osmotic pressure. It 

 has frequently been shown that the cell-walls do not lose their 

 semipermeable character until the death of the cell occurs ; 

 hence in cloudy swelling water diffuses in much more rapidly 

 than the crystalloids can diffuse out, 1 causing a hydropic swell- 

 ing. This hypothesis is supported by the observations of 

 Cesaris Demel, 2 who found that by modifying the osmotic con- 

 ditions of the cells, particularly epithelial cells, he could closely 

 reproduce many of the characteristic features of parenchymatous 

 degeneration. It is possible, also, that too high concentration 

 of crystalloids within the cells may be a factor in the precipita- 

 tion of the cell colloids. In view of the fact that in the earli- 

 est stages of autolysis histologic and microscopic changes closely 

 resembling those of cloudy swelling are pronounced, and that 

 organs the seat of cloudy swelling notoriously undergo autolysis 

 with extreme rapidity after death, we may also consider that 

 this process is possibly in part responsible for the change of 

 ordinary intra vitam cloudy swelling. The appearance of fine 

 granules of lipoid substance (myelin or " protagon " (?) ) in cells 

 during autolysis and during cloudy swelling is cited by Orgler 3 

 in support of this idea, and he found by chemical analysis of 

 organs showing cloudy swelling that there is definite evidence 

 of autolytic decomposition of the proteids and an increase in 

 the water content. 4 Landsteiner, through his studies of cloudy 

 swelling in human material also came to the conclusion that 

 autolysis is an important element in its production. 



"Waxy" degeneration of muscles, although usually result- 

 ing from the action of toxic substances, is entirely different from 

 cloudy swelling, in that the cytoplasm becomes homogeneous 

 and not granular. Dr. A. P. Mathews has suggested to me, 

 as a possible explanation, that the change is allied to the action 

 of acids upon fibrin, which causes the fibrin to swell up and 

 become homogeneous. As we know that abundant acid 



1 See introductory chapter concerning osmosis ; also discussion of edema. 



2 Lo Sperimentale, 1905 ; Cent. f. Path., 1905 (16), 613. 



3 Virchow's Arch., 1904 (176), 413. 



* Verb. Deut. Path. Gesell., 1903 (6), 76. 



