392 INTERNAL SECRETIONS OF PANCREAS AND SPLEEN. 



could but compromise the free circulation of the fluids, and, 

 simultaneously, the functional efficiency of the organ itself. 



THE SPLENO-PANCREATIC INTERNAL SECRETION. Resum- 

 ing the consideration of the relationship between the functions 

 of the two organs, spleen and pancreas, it is evident that each 

 possesses its own complete mechanism, and that in both organs, 

 as elsewhere in the economy, the oxidizing substance or the blood 

 containing it is the source of functional activity. 



Still, have we any reason to believe, with Popelski, that 

 it is through oxidation that the intrapancreatic trypsinogen be- 

 comes converted into trypsin? Can we say, for instance: the 

 intrapancreatic conversion of trypsinogen into trypsin is not 

 effected by the splenic ferment, but by the oxidizing substance, 

 when the efferent vagus nerves transmit appropriate impulses? 

 We think not, much as such a process would coincide with the 

 multiple functions that we have already ascribed to, the oxidiz- 

 ing substance. 



We have seen that when the pancreas becomes function- 

 ally active the extrinsic arteries are constricted beyond their 

 tonic caliber, and that the speed of the blood-flow through the 

 organ is increased. Yet, while the net-work of capillaries is 

 very rich, these encircle the secreting lobules, and, though in 

 close relation with the glandular epithelium beneath the base- 

 ment membrane, they in no way, as in the spleen, break up 

 into reticulated tissue wherein their blood is poured; they 

 merely lapse, as elsewhere in the organism, into venules, which 

 ultimately carry the blood to the larger venous channels. 

 Blood and trypsinogen do not come into contact, therefore, 

 in the ducts of the typical pancreatic lobule: that which text- 

 books employ to illustrate the origin, centripetal migration, 

 and functional elimination of the zymogen granules. These 

 are lost in the lobular lumina and ultimately reach the greater 

 duct on its way to the intestine, without apparently having 

 come into contact with the oxidizing substance. 



But, this being the case, how can we account for the ex- 

 perimental evidence adduced by Schiff and Herzen and other 

 physiologists who have confirmed their work? How can we 

 explain, for instance, the digestion of 17 grammes of albumin 

 in 7 hours with pancreas obtained from a normal cat and no 



