132 



DR RUTHERFORD ON THE INFLUENCE OF THE VAGUS 



nerve-fibres start from the parts to which the vagus is distributed, principally 

 therefore, from the stomach and lungs. 



Fig ' iS;7 Fa11 in . bl , ood :P res ! u f e on irritating upper end of vagus in a rabbit (both vagi divided) to which 10 milli 

 grammes of atiopia sulphate had been given. (Secondary 30 mm. distant from^prinSry coil One Danlell) 



Before — 



Stimulation of the Vagus. 



During- 



FIg ' !^ R i Se ^ blood -P r 1 essure / On irritating upper end of vagus in the same rabbit as that from which the fore- 

 going tracing was taken. (Secondary 120 mm. distant from primary coil. One Daniel].) 



Befbre- 



Stimulation of the Va^us. 



During- 



Having seen what are the effects upon gastric blood-vessels of division and 

 stimulation of the vagi, and also the changes which the latter gives rise to as 

 regards the blood-pressure, we shall now consider the effect of division of the 

 nerves as regards the blood-pressure. The experiments on each class of animals 

 are divided into two groups : 1st, those showing the effect of dividing the nerves 

 during digestion, and those showing the effect of this during fasting. The 

 main object of the whole being to ascertain whether or not during the former, 

 vaso-inhibitory influences are transmitted from the stomach through the vagi to 

 dimmish the action of the vasomotor nerves ruling over the gastric blood- 

 vessels, and thereby to bring about dilatation of these. While this is the main 

 point of the experiments, they at the same time furnish data which serve to 

 explain the acceleration of the pulse which sometimes follows division of the 

 vagi after paralysis of their cardio-inhibitory fibres (see page 122). 



