36 



Scientific Proceedings (125) 



12 (1972) 



The supposed relation of the adrenals to reflex volume changes 

 in the denervated limb. 



By G. N. STEWART and J. M ROGOFF 



[From the H. K. Cushing Laboratory of Experimental Medicine, 

 Western Reserve University, Cleveland, Ohio] 



Bayliss 1 showed that when the central end of a peripheral 

 nerve (sciatic) is stimulated the volume of a hind limb (dener- 

 vated by section of the anterior crural and sciatic nerves) in- 

 creases coincidently with the rise of blood pressure and then 

 diminishes to less than the initial volume. He explained the 

 dilatation of the limb as a passive dilatation due to the increase 

 of blood pressure and the subsequent constriction as a local re- 

 action, "the muscular coat of the arteries reacting, like smooth 

 muscle in other situations, to a stretching force by contraction." 



Von Anrep 2 stated that constriction of the limb never oc- 

 curred in the absence of the adrenals. He drew the conclusion 

 that it is due to a reflex increase in the epinephrin output, and 

 that the explanation of Bayliss was not satisfactory. 



We have reinvestigated the question in a series of about 50 

 animals, chiefly dogs. 



We find that a typical reaction can be elicited in acute experi- 

 ments after the adrenals have been clipped or tied or the glands 

 excised, in the great majority of dogs in which before interfer- 

 ence with the adrenals the reaction was present. In a certain 

 number of animals, the reaction has not been obtained by us 

 either before or after interference with the adrenals. Bayliss 3 

 seems also to have encountered animals in which similar reac- 

 tions were not obtainable. 



A considerable number of experiments were made on dogs 

 which had recovered from adrenal operations entailing marked 

 interference with, or suppression of the epinephrin output (re- 

 moval of one adrenal and the greater part of the other, with 

 curetting away of the remaining medulla and denervation of the 



1 Bayliss, J OW71. of Physiol., 1902, xxviii, 220. 



2 Anrcp, Journ. of Physiol., 1912-1913, xlv, 307, 318. 

 Bayliss, Journ. of Physiol, 1902, xxviii, 288. 



