THE ANTAGONISM BETWEEN THYROID 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 larv£e 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- 



1 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 n their new check list was 

 applied here. According to this the old species Amblystotna punctatiim corresponds 

 to the new species Anibystonia maculatum. 



25 



