Liver Blood of Diabetic Animals. 125 



After heating solutions consisting of equal volumes of a relatively- 

 pure glycogen solution and of saturated NaOH (purified by 

 alcohol) on the boiling water bath for periods exceeding three 

 hours, it was found that the glycogen could not be precipitated 

 by the addition of an excess of alcohol, unless the solution was 

 almost neutralized with HC1 and therefore contained an excess 

 of sodium chloride. In the above manner it was found that a very 

 high percentage all of added glycogen could be recovered. 



When blood that had been removed from the carotid artery 

 or portal vein of normal animals was treated in the above manner, 

 a small amount of highly colored precipitate separated out on the 

 addition of alcohol, but by redissolving this in boiling water after 

 thorough washing with alcohol, a solution was obtained which gave 

 only a faint opalescence on the addition of excess of alcohol and 

 of NaCl. In one or two instances it was possible to collect this 

 faint precipitate on a filter paper, but it was found to give no 

 coloration with iodine, and after hydrolysis to yield a solution 

 having no reducing properties. It probably consisted largely of 

 inorganic material. On the other hand, when the blood was 

 taken from the vena cava, opposite the point of entrance of the 

 hepatic veins, of sugar-fed dogs, rendered hyperglycemic either 

 by the injection of adrenin or by splanchnic stimulation, or from 

 the carotid artery of piqflre rabbits, a much larger amount of 

 precipitate was thrown down by alcohol (and NaCl), and after 

 repeated reprecipitation, and in one case after a second digestion 

 of the precipitate with half saturated NaOH, a pure white pre- 

 cipitate, amounting in one case to 0.0447 & m - after drying, was 

 secured. This precipitate still contained a considerable quantity 

 of alkali, etc., but when it was dissolved in water and the resulting 

 solution neutralized, a deep red violet color was obtained with 

 iodine (disappearing on heating and returning on cooling), and 

 the solution rotated polarized light to the right. On hydrolysis, 

 a solution was obtained that reduced Fehling's solution strongly, 

 and gave abundant osazone crystals, which, however, even after 

 recrystallization were mixed with so much amorphous material 

 as to make melting-point determinations useless. Larger quan- 

 tities of this polysaccharide are being collected for a more exact 

 study of its chemical relationships. 



