u EXTEENAL DIGESTIVE SECRETIONS 101 



De Doniinicis, and more recently Visentini and O. Hess, reply 

 in the negative. 



According to Hess the dog's pancreas often has more than 

 two ducts, hence the experiment of tying the two ducts is not 

 conclusive. According to Visentini the divided ducts can easily 

 recover their functions. But these authors neglect the fact 

 that alimentary absorption can also be beneficially affected by 

 the presence of a segment of the pancreas completely separated, 

 not only from, the duodenum (Abelnianu, Pfliiger, Hedon, U. 

 Lombroso, Eosenberg), but from the abdominal cavity as well 

 (U. Lombroso). 



Abelmann, Minkowski, Pfliiger, Eosenberg, supposed that 

 absorption in these last cases still depends upon the external 

 secretion, this being reabsorbed and carried by the circulation to 

 the liver or the intestinal glands, whence it is returned to the 

 intestine. 



Lombroso opposes this doctrine. He shows that by infusing a 

 certain quantity of pancreatic secretion into the vein, the enzy- 

 matic property of the bile might be profoundly altered for some 

 considerable time, whereas such modification does not occur after 

 occlusion of the orifices into the pancreas. He therefore thinks it 

 probable that in such cases there is no reabsorption of the pan- 

 creatic secretion. He has recently demonstrated (1908) in the 

 laboratory of Minkowski (who previously supported the opposite 

 theory) that a segment of pancreas, grafted under the skin, so that 

 its secretion is freely poured out externally, does promote food 

 absorption. Fleckseder, in Vienna, simultaneously arrived at the 

 same results as Lombroso, and therefore supports his theory. 



In view of these results it is no longer possible to put forward 

 alimentary absorption as a proof that the pancreas with occluded 

 ducts is capable of pouring the products of its external secretion 

 indirectly into the intestine. The internal function of the pancreas 

 must, therefore, be not solely the arrest of glycosuria, but also, 

 though indirectly, the promotion of food absorption. We shall 

 return to this subject in treating of the absorption of food. 



The next question is whether this internal function of the 

 pancreas connotes a special secretory process or no. Hedon holds 

 that it should be possible to prove the existence of an internal 

 secretory function of the pancreas, by the modification of experi- 

 mental diabetes with the introduction of glandular extracts into the 

 circulation, just as the thyreopriva syndrome can be modified by 

 administration of thyroid extracts. 



Eesearch in this direction has yielded only doubtful or contra- 

 dictory conclusions. Capparelli (1891-92) obtained favourable 

 results in depaucreatised dogs with injection of very fresh pan- 

 creatic pulp. Eecent observations of Ziilzer, Dohrn, and Maxer 

 (1908), on both human and experimental diabetes, had the same 



