METHODS OF OBTAINING PANCREATIC JUICE. 547 



Although, in the resting condition of the gland, an outer border free 

 from granules is evident, this is still more manifest in the exhausted 

 condition. The granules may then be so reduced in number as to form 

 small aggregations at the luminal borders only of the cells. 



As is the case in the stomach, there is reason to believe that the 

 granules are concerned with the specific secretion of the gland, the 

 amount of granules determining the activity of an extract. 



The above described changes in the cells were first observed in the 

 living pancreas of the rabbit by Klihne and Sheridan Lea. 1 



Methods of obtaining pancreatic juice. The methods that have been 

 adopted to procure a supply of pancreatic juice involve one of the following 

 procedures (a) Fixing a cannnla into the duct of Wirsung ; (ft) opening the 

 duct and connecting it with the body wall; (c) cutting out a piece of the 

 intestine in which the pancreatic duct opens, and fixing this to the body 

 wall. 



C. Bernard 2 adopted the first method, fixing a silver cannula into the duct. 

 Heidenhain 3 introduced antiseptic precautions into the operation. He made 

 an incision in the linea alba midway between the xiphoid process and the 

 umbilicus. The duodenum was drawn out through the opening and the duct 

 carefully sought for. This being found, into it was tied a glass cannula 

 of about 6-18 cms. in length. Around the intestine were placed two 

 temporary ligatures, keeping the gut closely applied to the body wall. The 

 opening was found to gradually close, allowing simply the cannula to pass 

 through. The second method was adopted by Ludwig with Weinmann, 4 and 

 Bernstein. 5 They found and opened the duct and inserted a piece of lead wire, 

 on the one hand, towards the papilla pancreatica in the duodenum, the other 

 end passing up to the gland substance. This wire did not fill the lumen, and 

 thus the flow was still permitted. The third method, which is due to Heidenhain 

 and adopted for permanent fistulse, consists in resecting the small portion of the 

 intestine which contains the papilla pancreatica, and joining the ends of the 

 main gut above and below. The piece of intestine is slit up, the mesenteric 

 surface is attached to the body wall, and thus the juice can be obtained. 

 Pawlow varied this method by not resecting the whole tube of the intestine. 

 He cut out a quadrangular piece, including the pancreatic papilla, and ligatured 

 this into the body wall. 



By these different methods natural pancreatic juice may be obtained. 

 After a time the juice becomes somewhat altered; it retains, however, its 

 ferment activity in a marked manner throughout. 



The influence of the nervous system upon pancreatic secretion. 

 Our knowledge has lately been considerably extended in respect of 

 the precise influence of nervous impulses upon pancreatic secretion. 

 The following statements summarise our chief knowledge up to the 

 most recent researches upon the subject. 6 



1. After division of the nerves, proceeding to the gland, secretion is set 

 up and apparently increases. This was affirmed by Bernstein. 7 



2. Secretion can be set up by stimulation of the medulla oblongata, 

 or, if already in progress, can be increased. 8 



3. The medulla oblongata must not be regarded as exclusively the 



1 Verhandl. d. naturh.-med. Ver. zu Heidelberg, N.F., Bd. i. 



2 " Memoire sur le pancreas et sur le role du sue pancre"atique," Compt. rend. Acad. d. sc. 

 Paris, 1856. 



3 Hermann's " Handbuch," Bd. v. 4 Ztschr. f. rat. Med., Bd. iii. 



5 Ber. d. k. sacks. Gesellsch. d. Wissensch., Leipzig, 1869. 



6 Cf. Heidenhain, Hermann's "Handbuch," Bd. v. Abth. 4. 7 Op. cit. 

 8 Heidenhain, Arch. f. d. ges. Physiol., Bonn, 1875. 



