126 



DR RUTHERFORD ON THE INFLUENCE OF THE VAGUS 



Influence of the Vagi upon the Blood-vessels of the Stomach. 



Effect of Division and Irritation of the Nerves, 

 (a.) During Digestion. 



Experiment XXIV. — Eabbit two months old. Three hours after food was 

 given the vagi were exposed, and the trachea opened in order to prevent 

 asphyxia and consequent struggling. The abdomen was opened, and the 

 stomach found to be largely distended with food, and its outer surface very 

 vascular. Intestines were moderately vascular. The stomach was then opened 

 by an incision extending from right to left along its anterior surface, and its 

 contents partially everted. The lining membrane was of a dusky red hue. The 

 vagi were divided in the neck four minutes after the exposure of the gastric 

 mucous membrane. Pallor of the membrane followed immediately upon the divi- 

 sion of the nerves, and remained during the time occupied by the rest of the 

 experiment — forty-five minutes. The superior cardiac branches of the vagi 

 (depressor nerves) were then divided ; the result was a slight increase in the 

 pallor of the mucous membrane. 



The effects of irritating the vagi were now attended to. The irritant used 

 was Faradic Electricity from Du Bois Keymond's machine, with 1 Smee's cell. 



Time after Division 

 of Vagi. 



Distance of Primary from 



Secondary Coil of Machine 



in Millimetres. 



Nerve Stimulated. 



Result as regards redness of 

 Gastric Mucous Membrane. 



10' 



230 



Upper end left vagus. 



No evident change. 



12' 



180 



Upper end left vagus. 



Became redder. 



13' 



10 milligrammes atr 



opiae sulph.* given to paralyse cardio-inhibitory fibres 







of vagus. 





15' 



180 



Lower end left vagus. 



No evident change. 



21' 



120 



Upper end right vagus. 



Pallor followed by slight 

 redness. 



25' 



80 



Upper end right vagus. 



Pallor. 



34' 



70 



Lower end right vagus. 



No evident change. 



44' 



70 



Lower end left vagus. 



No evident change. 



Experiment XXV. — Full-grown strong rabbit fed two and a half hours 

 before the experiment was begun. Abdomen opened ; stomach and intestines 

 very vascular. Division of the vagi was followed by decidedly diminished 

 vascularity of the outer surface of the stomach which was in this case unopened. 

 Owing to an interruption the experiment was not carried beyond this point. 



Although this substance paralyses the eanfoo-inhibitory, it does not paralyse the waso-inhibitory 



nerves. 



