422 RETROGRnSSIVE CnAXGES 



cause amj'loidosis experimentalh' in animals, especially chickens and 

 rabbits, by causing protracted suppuration or chronic intoxication 

 with bacterial filtrates, these negative results speak strongly against 

 the idea of a transportation of chondroitin-sulplmric acid, but do not 

 detenuine it finally. They may also, with propriety', be used in sup- 

 port of the statement of Hanssen that amyloid does not contain chon- 

 droitin-sulphuric acid. There is usually much difficulty in producing 

 amyloid experimentally, for in only a certain proportion of cases are 

 the experiments positive (in but about one-third of Davidsohn's- 100 

 trials, and many other experimenters have been much less successful ) .^ 

 Davidsohn, failing always to get amyloid experimentally after the 

 spleen had been removed, suggests that this organ (in which amyloid 

 is usually earliest and most abundantly observed) produces an enzyme, 

 which causes a precipitation of amyloid in the tissues from a soluble 

 precursor brought in the blood from the site of cell destruction. 

 Schmidt * considers it probable that some enzymatic action causes a 

 precipitation or coagulation of the substance in the tissue-spaces or 

 lymph-vessels. Amyloid is never deposited in the cells themselves,*^ 

 and it seems to be now generally considered that the amyloid material 

 is infiltrated in the form of a soluble modification or precursor and 

 that it is not manufactured in the organ where it is found. It is an 

 interesting fact that a practically identical substance is formed in all 

 tissues and in all species of animals, even when the cause is quite dif- 

 ferent. Whether the precursors are brought to the organ in solution, 

 or in leucocytes, is unknown — probably the former. Pollitzer ^ states 

 that in various infections, especially coccus infections, chondroitin- 

 sulphuric acid is excreted in the urine ; if this is correct it has an 

 undoubted bearing on the genesis of amyloidosis. The presence of 

 glycothionic acid in pus ^ is of similar significance. The hypothesis 

 that amyloid is formed from disintegrating red corpuscles is probably 

 incorrect. Ann'loidosis is produced by the most varied species of 

 bacteria and by their toxins, although the staphylococcus is usually 

 most effective in experimental work.'^ Neither is suppuration abso- 

 lutely essential, for injection of toxins alone {e. g., in preparing diph- 

 theria antitoxin^), without suppuration, may produce amyloidosis, as 

 iilso frequently does syphilis without suppuration and, less often, 

 many other non-suppurative conditions {r. rj., tinnors). 



2 Verb. Deut. Path. Gesell., 1904 (7), 39. 



3 See Tarchetti, Deut. Arch. klin. iled.. 1903 (75), 526. 



4 Verb. Deut. Path. Cesell., 1904 (7), 2. 



4a See Ebert, A'ircliow's Arch., 1914 (216), 77. 



•-'Deut. med. Wocb., 1912 (3S), 1538. 



<i .Mandel and Levene, Tiidchciii, Zcit., 1907 (4), 7S. 



" In a series of experiments directed to ascertain, if p()ssihU\ wliich constituent 

 of pus niifjlit he tlic^ cause of amyloid formation, 1 was unable to secure amyloid 

 by i)rotracted intoxication of ral>bits bv Witte's "peptom\" which consists chiellv 

 of proteoses (Trans. Chicafjo Path. Soc., 1903 (5). 240). 



8 See Lewis, Jour. Med. Research, 1906 (15), 449. 



