CHAP. IX.] CONDITIONS INFLUENCING SECRETION OF INTES. JUICE. 409 



absence of stimuli and in the lasting condition, but the secretion 

 became much .more abundant after food. Thiry 1 , Quincke 2 , Masloff 3 , 

 Gumilevvski 4 , Vella 5 , all substantially agree in stating that in the 

 absence of stimuli the secretion of the intestinal juice is either in 

 abeyance or at most very scanty. Whether the secretion be com- 

 pletely absent or only scanty, during the resting and fasting con- 

 ditions, there can be no doubt that after food has been taken secretion 

 occurs, though not immediately, the amount probably increasing up 

 to the 6th or 7th hour of digestion 6 . We are not as yet in possession 

 of data as to the amount of secretion poured out by different segments 

 of the intestinal mucous membrane during the digestive act. The 

 difficulties of the investigation are remarkably great and, indeed, 

 appear almost insuperable. It is obvious that the secretion poured 

 out, during digestion, by an isolated portion of the intestine which is 

 not affected by the normal stimulus afforded by the intestinal con- 

 tents can only imperfectly, if at all, quantitatively represent the 

 process going on in the rest of the intestine. 



Rohmann, from comparative observations on three dogs with 

 Vella-fistulse, as well as from an examination of the data of previous 

 observers, has established a strong presumption in favour of the view 

 that the secretion of intestinal juice is much more abundant in the 

 lower than the upper part of the small intestine 7 . 



Effects of me- The mere introduction of a catheter or pieces of 

 chanicai and S p 0nge i nto t h e gut, through a Vella-fistula, is sufficient 

 electrical sti- ',. 5- , . , ,. , . . mi 



muiationofthe to P rov ke a secretion of the intestinal juice. Ihe 

 mucous mem- mucous membrane forming the edges of the fistula 

 brane. becomes injected and from time to time small drops of 



liquid, mixed at first with masses of mucus, rich in exuviated 

 epithelium, exude. The amount and character of the mucus depend, 

 in no small degree, upon the intensity of the stimulant, which very 

 readily gives rise to a pathological reaction. 



Thiry, by mechanical stimulation of a fistula, obtained from a 

 surface of intestine estimated at 30 square centimetres, secretion at 

 the rate of 4 grms. per hour. Other observers obtained smaller 

 amounts ; but the data possess no value, seeing that the stimuli were 

 of unknown intensity and provoked a secretion which was probably 

 abnormal in amount, and certainly abnormal in character. 



1 Thiry, ' Ueber eine neue Methode, &c.' (see p. 406). 



2 Quincke, ' Ueber die Ausscheidung von Arzneistoffen durch die Darmschleim- 

 haut,' Archivfiir Anat. u. Physiol. 1868, pp. 150164. 



3 A. Masloff, ' Zur Diinndarmverdauung,' Untersuchungen a. d. physiol. Institute zu 

 Heidelberg, n. (1882), pp. 290306, see p. 300. 



4 Gumilewski, Pfliiger's Archiv, Vol. xxxix. (1886), p. 556. 



5 Vella, op. cit. (see references, p. 406). 



6 Heidenhain, ' Physiologic d. Absonderungsvorgange,' Hermann's Handbuch, Vol. v. 

 i. p. 170. 



7 Dr F. Rohmann, 'Ueber Secretion uud Resorption im Diinndarm' (Aus d. physiol. 

 Institut zu Breslau), Pfliiger's Archiv, Vol. XLI. (1887), pp. 411462. 



