LABORATORY MANUAL OF PHYSIOLOGY. 



Feed another cat, after a starvation period of twelve hours, with 

 fatty meat or milk and cream. Kill in ten hours after the meal. 

 Prepare the intestinal mucous membrane, as before, with osmic 

 acid. Also note the appearance of the lacteals. Can you demon- 

 strate the presence of fat in the intestinal epithelium ? 



VII. MECHANISM OF PANCREATIC SECRETION. 

 (DEMONSTRATION.) 



i. Narcotize a medium-sized dog with morphine sulphate and 

 anaesthetize with ether. Expose and introduce a cannula into the 

 trachea. Expose, isolate, and secure both vagus nerves with un- 

 tied ligatures. Connect the tracheal cannula with the artificial re- 

 spiratory apparatus and anaesthetic flask. Through a median ab- 

 dominal incision expose the duodenum and head of the pancreas. 

 Slit the duodenum longitudinally for an inch or more in the neigh- 

 borhood of the head of the pancreas. Place a cannula in the larger 

 pancreatic duct through its duodenal opening, on a level with the 

 lower border of the pancreas. Connect this with a long glass tube, 

 bent so as to pass over the edge of the abdominal wound. Fill this 

 tube with physiological salt solution. 



To the rubber membrane of a transmitting tambour cement a 

 light aluminum shovel-shaped lever. Arrange the transmitting 

 tambour in connection with a recording and a slow drum. Bring 

 the end of the pancreas-cannula tube over the shovel lever of the 

 tambour. Each drop from the end of the cannula will then depress 

 the lever of the transmitting tambour, and this will be transmitted 

 to the recording tambour and a record will be written on the paper 

 of the revolving drum. 



During the continuation of the experiment the exposed abdom- 

 inal viscera should be protected by cotton pads soaked in warm 

 o.8-per-cent NaCl solution. 



After completion of the operative procedures, note the rate of 

 flow of pancreatic juice for a period of ten or fifteen minutes. Now 

 inject into the duodenum or jejunum 30 c.c. of a o.4-per-cent HC1 



