THE INTERNAL SECRETION OF THE PANCREAS 413 



in the urine and by all those further symptoms (polyuria, poly- 

 phagia, emaciation ending in death) which we are accustomed to 

 associate with pronounced diabetes mellitus. An intimate rela- 

 tionship between diabetes and pancreatic disease had already been 

 suspected by several clinicians, who, upon anatomical grounds, 

 ascribed a pathogenetic significance to the pancreas in that 

 condition. Their hypothesis was now supplied with an experi- 

 mental foundation, while at the same time a new and previously 

 unknown function of the pancreas was brought to light. 



A similar discovery to that of v. Mering and Minkowski was 

 made, at about the same time and quite independently, by de 

 Domenicis, though he failed to recognize the significance of his 

 findings. The results have since been confirmed by means of 

 many hundreds of experiments, undertaken by numerous authors 

 (Lepine, Hedon, Gley, Thiroloix, Caparelli, Harley, Schabad, 

 Cavazzani, Sandmeyer, Selig, Rumboldt among others). 



That glycosuria is a constant finding after extirpation of the 

 pancreas was disputed by isolated authors, but these exceptional 

 cases are fully explained by the, at first sight, remarkable fact, 

 that characteristic sequela? are observed only after complete, or 

 almost complete, extirpation of the organ. If one-third to one- 

 fifth of any part of the gland is left in situ, glycosuria will not 

 appear. If the remnant becomes destroyed by secondary pro- 

 cesses, or is removed by surgical means, serious diabetic sym- 

 ptoms will make their appearance. These observations pointed to 

 the fact that the cause of the metabolic derangement could not lie 

 in the digestive disturbances arising from the absence of the 

 pancreatic juice ; they -showed, moreover, the relative unimpor- 

 tance of the changes brought about by operative intervention, in 

 the conditions governing the blood supply and the innervation 

 of the organ. Minkowski, followed by E. Hedon, whose work, 

 however, was quite independent, next showed by a well planned 

 series of experiments, that neither lesion of the vessels nor of the 

 nerves, nor suppression of the external secretion of the organ, is 

 the causative factor in the production of pancreatic diabetes. The 

 method employed was to remove that portion of the pancreas of 

 the dog which is situated in the mesentery of the duodenum, and 

 which Pfliiger named processus uncinatus, and to implant it, 

 together with its vascular peduncle, under the skin of the 

 abdomen. If this transplanted portion is sufficiently vascularized 

 and nourished, the rest of the pancreas may be removed by a 

 second operation without producing diabetes. But if, by a third, 

 very slight extraperitoneal operation, the transplanted portion of 

 the pancreas is also removed, serious diabetes will follow, and 

 death will ensue. 



As the result of these experiments, pancreatic diabetes became 

 the subject of eager experimental investigation. Total extirpation 

 of the pancreas was next carried out with animals of different 



