42 



Scientific Proceedings (31). 



perimental work are only in most exceptional instances without 

 defects or errors. 



Such a defect in the connexus of cause and effect has recently 

 been brought to my knowledge and, today, makes it debatable 

 whether the name " hormon " is correctly applied by myself to 

 the stimulating quality of one gland extract upon the secretion 

 of another set of glands. The definition and conception of the 

 hormon allows a rather wide application, it is true, but it seems 

 to me it ought to be restricted to substances whose chemical 

 structure is at least approximately known and that have one pre- 

 dominant characteristic or specific effect on other glands, in which 

 effect they cannot be replaced by extracts from other organs or 

 tissues. This is not the case with the salivary extracts, for, as we 

 can learn {Biochem. Zeitschr., Vol. xi, p. 253), extracts of the 

 pyloric mucosa and of the spleen (Luciani) act in a similar manner 

 in stimulating gastric secretion. 



Concerning the pepsinogenous effect of the spleen on the gas- 

 tric secretion, I refer to the work of Tarulli and Pascucci, executed 

 in Luciani's laboratory and described in the latter's splendid 

 work, " Physiologic des Menschen," translated into German by Bag- 

 lioni and Winterstein, Vol. ii, pp. i 5 i and 152. On page 1 53 it will 

 be seen that the extract must be made from an active spleen, as 

 Luciani says "a spleen that is hyperemic and swollen," which 

 means, taken from a dog during the height of the digestive period. 

 Extracts of spleen taken during the period of functional rest had 

 no pepsinogenous effect ; but the meaning of Luciani and his pupils 

 above mentioned is unmistakable. A chemical substance is formed 

 in the spleen during its activity which, when brought into the circu- 

 lation, is absorbed by the gastric glands and is capable of aug- 

 menting the quantity of the secreted pepsin. Additional emphasis 

 is given in these experiments to the fact that the extract should 

 only be made from a functionally active gland. 



Whatever may be the final outcome of investigations concern- 

 ing the chemical nature of the hormones, Bayliss and Starling 

 consider that they were originally accidental by-products of the 

 activity peculiar and proper to the organ which has produced them. 

 Thereafter the next step in the development of a correlation is the 

 acquisition of a sensitiveness or a responsiveness to the hormones 



