532 DIABETES 



But, in its cardinal features, human diabetes most generally 

 resembles pancreatie diabetes, and in a large proportion of the 

 cases lesions of the pancreas are found present. These are not 

 always marked, however, and they are by no means constant. 

 Opie, in particular, has brought forward evidence that diabetes 

 is frequently associated with lesions of the islands of Langer- 

 hans, whereas extensive lesions of the pancreas which do not 

 involve the islands (e. y., sclerosis and atrophy following 

 occlusion of the pancreatic duct) do not cause diabetes. This, 

 of course, suggests that the islands of Langerhans produce the 

 internal secretion of the pancreas that has to do with sugar 

 metabolism. The full evidence on this point will be found in 

 Opie's work on " Diseases of the Pancreas." However, there 

 occur many cases of diabetes in which no anatomical changes 

 whatever can be found in the pancreas, and others in which the 

 lesions in the parenchyma far outweigh those of the Langer- 

 hans islands. 1 Still another fact of significance in this connec- 

 tion is that organotherapy, by means of pancreas preparations, 

 has given no favorable results in diabetes, even when the 

 diabetes has been unquestionably of pancreatic origin. 2 



We must, therefore, recognize the probability that pancreatic 

 disease is not the sole cause of diabetes and that the importance 

 of the islands of Langerhans is not finally established, while at 

 the same time recognizing the fact that failure to detect ana- 

 tomical changes does not always prove the absence of func- 

 tional impairment. 



The glycosuria, which is the most characteristic, but by no 

 means the sole, important feature of diabetes, is dependent upon 

 hyperglycemia. The amount of sugar in the blood is often 

 as much as three parts per thousand, instead of one part as nor- 

 mally, and may reach 7 to 10 parts; however, the amount of 

 sugar in the urine does not by any means vary directly with 

 the amount in the blood. This hyperglycemia is remarkable in 

 that, at least in the advanced stages of diabetes, it persists even 



1 For the evidence against the view that the islands of Langerhans are the 

 chief factor in pancreatic diabetes see Herxheimer, Virchow's Arch., 1906 

 (183), 228. 



2 Moore, Edie, and Abram (Biochem. Jour., 1906 (1), 28 and 446) have 

 obtained a favorable influence in certain cases of diabetes by stimulating the 

 pancreas through administration of secretin obtained in duodenal extracts. 

 Secretin is a secretion of the upper part of the small intestine, which has 

 the property of causing a greatly increased flow of pancreatic juice. Pre- 

 sumably it produces its effect in diabetes by increasing the internal secretion 

 of the pancreas. Bainbridge and Baddard (Biochem. Jour., 1906 (1), 429) 

 found the secretin content of the intestinal mucosa greatly decreased in 

 human diabetes, although unable to obtain favorable clinical results by 

 administration of duodenal extracts. 



