THE ANTAGONISM BETWEEN THYMUS AND 

 PARATHYROID GLANDS. 



By EDUARD UHLENHUTH. 



(From the Laboratories of The Rockefeller Institute for Medical Research) 

 (Received for publication, July 16, 1918.) 



INTRODUCTION. 



• It is well known that the extirpation of the parathyroids in mam- 

 mals is followed by tetanic convulsions. This led to the conclusion 

 that certain tetany-producing toxins are formed in the body, which in 

 normal animals must be either removed or turned into non-toxic sub- 

 stances by the parathyroid glands. The origin of these toxic sub- 

 stances, however, is unknown. Though tetanic convulsions and 

 other symptoms of tetany have been reported repeatedly to occur 

 after injection of thymus extracts, in the frog as well as in mammals,^ 

 no attention has been paid to this fact as possibly containing the solu- 

 tion of the problem in which organ the tetany-producing substances 

 might be manufactured. The experiments presented in this article 

 seem to indicate that they are contained in and produced by the thy- 

 mus gland. This harmonizes with the well known fact that tetany 

 is a disease of infants. 



In the spring of 1916, about thirty salamander larvae of the species 

 Amby stoma maculatum^ were fed exclusively on calf's thymus. Each 

 single larva after some time began to suffer from severe tetanic at- 

 tacks. Since the larvae of salamanders do not possess parathyroids 

 this observation seemed to be of considerable interest, and, in the fall 

 of 1916, calf's thymus was fed to larvae of another species of sala- 



^ See Biedl, i, 279, 301 ff. 



^ In the terminology to be employed in the classification of amphibians the 

 nomenclature as worked out by Stejneger and Barbour in their new check list was 

 applied here. According to this the old species Amblystoma punctatum corresponds 

 to the new species Ambystoma maculatum. 



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