CIIOLIM-: a ROUP 123 



Putrescine, C^HjoN^,, structural formula, 



NH,— CH„— CH:;— CH„— CH,— XI r,, 



and cadaverine, C-II14N.,, structural formula, 



NHo— CHo— CH,— CH,— CH,— CH,— NH„ 



are of interest because they have been found in the intestinal con- 

 tents, arising" from putrefaction of proteins, and also are sometimes 

 present in the urine in cystinuria.''' They are closely related to the 

 diamino-acids, lysine and ornithine. They are but slightly toxic, 

 although capable of causing local necrosis when injected subcutane- 

 ously. (See further discussion on these and the Pressor Bases in 

 Chap, xix.) 



The Choline Group. — Another group of ptomai'ns, including choline 

 and closely related substances, is also of interest. These ptomai'ns 

 are: 



Choi ine, CH^OH— CH„— X ( CH3 ) 3— OH 



Xeurine, CH„=CH— N ( CH, ) 3— OH 



IMuscarine, CH ( OH ) ,— CH„— X ( CH, ) 3— OH 



Betaine, COOH— CH,— X^ ( CH3 ) 3— OH 



The first point of importance is that choline is present in every 

 cell normally, forming the nitrogenous portion of the lecithin mole- 

 cule. Its source in putrefaction of tissues is, therefore, plain. It is 

 possible' that choline is liberated from nerve tissues when they break 

 down in the body during life,'^® and there is a considerable literature 

 on the supposed finding of choline in the blood and cerebrospinal 

 fluid in diseases of the central nervous system and experimental 

 lesions in nervous tissues. At present it seems probable that these 

 observations depend upon faulty methods of analysis, and it is ex- 

 tremely doubtful if enough choline is ever set free at one time from 

 even severe acute nervous lesions to be detected in the body fluids by 

 chemical means.'^" Hunt ''-'' has devised a physiological test that per- 

 mits of the detection of as little as 0.00001 mg., but he was unable to 

 obtain evidence that choline is of any significance in either physiologi- 

 i^al or pathological processes. Normally the largest amounts by far are 

 obtained from the adrenals, which also seem to contain choline deriva- 

 tives of much greater physiological activity. Choline itself is some- 



73Udranszkv and Baumann, Zeit. phvsiol. Chem., ISSn (1.3), 562: 1880 (15), 

 77. 



70 Coriat (Amor. Jour, of Physiol., 1904 (12). .35.3) has studied the conditions 

 \inder wliich choline niav lie produced from lecitliin. Putrefaction of lecitliin 

 or lecithin-rich tissues liberates choline, as also does autolysis of brain tissue; 

 neither pepsin nor trypsin, however, splits it from the lecithin. Tn brain tissue, 

 therefore, there seems to be an enzyme different from trypsin, whicli splits 

 choline out of the lecitliin molecule. 



77 See Webster, Biocliem. .Tour., inon (4), 123; Kajiura, Ouart. Jour. Exper. 

 Physiol., inOS (1), 201; Handelsmann, Dent. Zeit. Xervenheilk., 1908 (35), 428; 

 Doree and Golla, Biochem. .Jour., 1910 (5), 306. 



77a Jour. Pharmacol., 1915 (7), 301. 



