466 G ASTRO-INTESTINAL "AUTOINTOXICATION" 



absorbed and eliminated as urobilin. Icterus and cholemia do 

 not seem ever to be produced by absorption of bile-pigments and 

 bile salts from the intestines. (See Icterus, pp. 405-410.) 



IL PRODUCTS OF NORMAL DIGESTION 

 Proteoses and Peptones. Under normal conditions, 

 these are broken up in the intestinal wall into the amino-acids, 

 through the agency of erepsin, and do not appear in the blood 

 in appreciable quantities. To be sure, certain authors claim to 

 have found albumose in normal blood, 1 but if present the amounts 

 are extremely minute. In conditions in which ulceration or other 

 lesions are present in the gastro-intestinal tract it is possible to 

 find small amounts of proteoses in the urine, probably absorbed 

 through the abnormal areas, but not in quantities sufficient to 

 account for any appreciable intoxication, although proteoses are 

 distinctly toxic. This last statement has been much contested, 

 because the difficulty of purifying proteoses obtained from ordi- 

 nary sources has left open the possibility that such toxic effects 

 as have been observed are due to contaminating substances, and 

 not to the proteoses themselves. More recent work, however, 

 particularly that of Under hill, 2 seems to have established affirm- 

 atively the toxicity of proteoses, whether from animal or vege- 

 table proteids. Besides the classical effect of inhibiting the 

 coagulation of the blood, the proteoses have a lymphagogue 

 effect (Heidenhain 3 ), cause a fall in arterial pressure, cause a 

 marked febrile reaction, and in doses of some size are fatal to 

 experimental animals (rabbits being much less susceptible than 

 dogs and many other animals 4 ). Locally they cause a mild in- 

 flammatory reaction, which is followed by the appearance of much 

 connective-tissue formation. 5 



1 Embden and Knoop, Hofmeister's Beitr., 1902 (3), 120; Langstein, ibid., 

 p. 373; Morawitz and Dietschy, Arch. exp. Path., 1905 (54), 88. However, 

 many investigators have failed to find them; see Abderhalden and Oppen- 

 heimer, Zeit. physiol. Chem., 1904 (42), 155 ; Schryver, Biochemical Journal, 

 1906 (1), 137; Kraus, Zeit. exp. Pathol., 1906 (3), 52. 



2 Amer. Jour. Physiol., 1903 (9), 345 (literature). 



3 See also Nolf, Arch, internat. de Physiol., 1906 (3), 343. 



4 According to Buchner and Geret, Munch, med. Woch., 1901 (48), 1163 r 

 0.2 gram of " pure peptone " per kilo kills rabbits in twelve hours. 



5 In a paper appearing in the Transactions of the Chicago Pathological 

 Society, 1903 (5), 240, I published the observation that repeated injections of 

 Witte's "peptone" (which consists chiefly of proteoses) into rabbits led to the 

 production of marked cirrhosis of the liver, and suggested the possibility that 

 proteoses escaping through a diseased gastric or intestinal wall into the blood 

 might be a factor in the production of cirrhosis in man. Subsequent observa- 

 tions, however, have shown that repeated injection of almost any foreign pro- 

 teid material (e. g., emulsions of organs, foreign blood, etc., used in immuniza- 

 tion experiments) will cause a similar cirrhosis in rabbits, which animals, 



