188 



Scientific Proceedings (76). 



sure caused by the liberated epinephrin, occurring at a definite 

 interval after release of the pocket, can be identified by the fact 

 that the eye reaction also commences at or about this moment. 

 However, to further strengthen the evidence we have made experi- 

 ments in which the celiac and superior mesenteric arteries are first 

 tied off, then the renal arteries, and then the abdominal aorta just 

 below the kidneys. As much blood as possible is got into the 

 anterior end of the animal, and then the inferior cava is tied above 

 the iliacs. The renal veins are then ligated, and the cava pocket 

 now represents only a blind pouch upon the circulation, the filling 

 of which from the adrenal veins, or the emptying of which after 

 removal of the upper clamp produces relatively little mechanical 

 effect upon the blood pressure. The lower end of the animal is 

 kept raised throughout the experiment. This facilitates emptying 

 of the pocket without manipulation. 



4. In different experiments we have assayed, by the injection 

 of known quantities of adrenalin, the amount of epinephrin 

 liberated without artificial stimulation of the splanchnics, under 

 our experimental conditions (narcosis with urethane alone, and 

 with urethane supplemented with ether). For example, in one 

 experiment we found 0.0005 m g- an d in another 0.0009 m S- P er kg. 

 of animal, per minute. When the pocket is allowed to fill during 

 stimulation of the splanchnics, with intervals of rest, the effect 

 on release is distinctly greater than when it is allowed to fill for 

 the same time without artificial stimulation of the nerves. 



5. We have endeavored to measure the amount of blood 

 collected in the pocket, without bringing it into contact with any 

 foreign substance, in the following way: One of the iliac veins is 

 tied near its distal end and the other near the cava. Both iliacs 

 are then divided distal to the ligatures. By means of the ligature 

 on the first iliac it is suspended vertically, while the greater part 

 of the cava segment lies undisturbed. The iliac vein thus serves 

 as the neck of a measuring flask, so to say, the body of which is 

 composed of the cava segment. It is not difficult to determine 

 the moment when the blood, entering the pocket practically 

 without resistance, the walls of the vein being scarcely at all 

 distended so long as the vertical portion of the pocket is empty, 

 just reaches the proximal end of the iliac. If undue exposure of 



