G. N. STEWART 



auto-assay by means of blood-pressure tracings either in the cat (Fig. 14) 

 or in the dog (Fig. 15). Gley and Quinquaud(e) found that in prolonged 



Fig. 15. Blood pressure curves from dog. At 46, a cava pocket which had been 

 closed for 3 minutes was released. At 48, a cava pocket which had been closed for 3 

 minutes during asphyxia was released. Asphyxia was stopped more than half a minute 

 before the pocket was opened. There is no essential difference in the two curves. Time 

 trace, seconds. 



asphyxia a marked increase in the concentration of epinephrin in the 

 blood of the suprarenal vein occurs. But this is simply because the blood 

 flow is correspondingly reduced, the output being unchanged. The central 



Fig. 16. Blood pressure curves from a cat after section of the vagi and excision 

 of the stellate ganglia. The right suprarenal had been removed and the left suprarenal 

 denervated 34 days previously. A, sciatic stimulation before and /?, after excision of 

 the remaining (already denervated) suprarenal; f, after subsequent section of the 

 remaining (right) splanchnic. The numbers show the pulse rates. Decided accelera- 

 tion of the heart was caused by stimulation of the central end of the sciatic both before 

 and after removal of the left suprarenal. Accordingly this could not have been due to 

 increased epineplirin output. When the blood pressure was diminished by section of 

 the only intact splanchnic nerve the reaction practically disappeared. Time trace, 

 seconds. (Reduced to three-fifths.) (After Stewart and 'Rogoff, Am. J. Physiol.) 



nervous mechanism controlling the epinephrin secretion is accordingly not 

 easily stimulated by asphyxia, at least in anesthetized animals, Whether 



