1907.] The Pressure of Bile Secretion, etc. 531 



The form of the curves of bile pressure shows that there is not much 

 absorption until the pressure has reached about 100 mm. bile. The rate of 

 rise of pressure then begins to diminish more rapidly in some cases than in 

 others. Absorption is at first slow, but gradually increases until its rate is as 

 rapid as the rate of secretion when the column of bile becomes stationary. 



On the death of the animal, the bile pressure, if high, sinks rapidly at 

 first, but on approaching a pressure of about 100 mm. falls much more slowly 

 and becomes almost stationary. The same thing occurs even if death has 

 been caused by opening the inferior vena cava above the diaphragm. Blood 

 pressure in the liver rapidly falls to zero, but the bile pressure falls slowly. 

 The curve of fall of bile pressure after death is given on the chart. 

 In Cat O, the sudden fall of bile pressure near the end of the tracing is due 

 to death from an overdose of chloroform. When the pressure had fallen 

 to 149 mm. bile, the inferior vena cava was divided above the diaphragm ; 

 bile pressure fell very slowly, and six minutes later was 134 mm. In 

 Cat P, death was brought about by division of the inferior vena cava, and 

 the pressure of bile secretion, which was 276 mm. at the time, fell rapidly at 

 first, then at a decreasing rate. Ten minutes after the vein had been opened 

 the bile pressure was 108 mm., and falling very slowly. If the bile had been 

 escaping from ruptured bile ducts into the lymphatics or into the blood 

 vessels, it is improbable that this slowing of the fall of pressure would have 

 taken place. 



The absorption of bile seems to us to be bound up with the formation of 



lymph in the liver, and while we advance no definite proofs in favour of 



Asher's view, we are inclined to think that the phenomena observed in the 



absorption of bile can best be explained on the hypothesis that lymph is a 



product of the activity of the liver cells, and that in obstructive jaundice the 



bile secreted leaves the liver cells with the lymph, instead of by its proper 



channels, the bile canaliculi. 



Summary. 



The maximum pressure reached by the bile in obstruction of the bile duct 

 exceeds the figures originally given by Heidenhain. In the dog, cat, and 

 monkey the average maximum pressure is about 300 mm., measured in terms 

 of a vertical column of bile. The highest pressure recorded was 373 mm. 

 bile in a cat. In the ordinary rabbit the pressure reaches about 200 mm. bile, 

 but may exceed 300 mm. in the case of the Belgian hare. 



After obstruction of the common bile duct and cystic duct, the pressure 

 in the bile passages rises rapidly at first, but slows as a maximum is reached. 

 Subsequent records of bile pressure after temporary release of the bile may 

 exceed the first maximum, but are usually lower. After death the bile 



