io8 



THE DISEASES OF THE THYROID GLAND 



A diminution in the excitability of the vegetative nervous system is 

 demonstrated also by the experimental investigations in thyroidless animals. 

 i'. Cyon found a diminution of the excitability to electrical stimulation of 

 the vagi nerves in such animals. The hyperexcitability of the accelerator 

 nerves that he asserted to be present could not be confirmed. It is far more 

 likely that the excitability of the sympathetic nerves is diminished. For 

 this view speaks the failure of the glycosuric action of adrenalin in thyroid- 

 ectomized animals and in myxedema patients. As regards the diminution 

 of the pressor action of adrenalin we (Eppinger, Folia, and Rudinger) did not 

 arrive at a certain result; while on the contrary, later investigations of 

 Bertelli and myself show definite alterations in the reaction of the vascular 

 system of thyroidless dogs against adrenalin. 



As I regard the experiments important, I shall quote them in extenso. 

 15 kg. dog, ten days ago total extirpation of the thyroid gland with 

 avoidance of the parathyroids. Electrical excitability remains unaltered. 



Erythrocytes 



Hemoglobin 



Specific gravity 



Before the injection 



5 hours after the infusion of 3.69 mg. adrenalin 

 24 hours after this 



4,900,000 

 4,100,000 

 3,936,000 



45 per cent. 

 45 per cent. 

 45 per cent. 



1054 

 1050 

 1051 



Dog, 16 kg., total extirpation of the thyroid six weeks ago. Electrical 

 excitability remains unaltered. 



Erythrocytes 



Hemoglobin 



Specific gravity 



According to investigations of Bertelli, Schweiger, and myself, the erythro- 

 cyte count in normal dogs after the injection of adrenalin increases extra- 

 ordinarily rapidly; after ten minutes it may reach 40 per cent., after five 

 hours 70 per cent. In an experiment in which 4.36 mg. adrenalin was 

 injected, it reached 100 per cent, after twenty-four hours; in another 

 experiment after 3.69 mg. the hyperglobulia was indeed distinct, but had 

 already begun markedly to decline. Although of course there occurred indi- 

 vidual differences in the intensity and duration of the reaction, there was to 

 be observed in all normal dogs a distinct rise. The hemoglobin contents 

 showed a very much less increase. The specific gravity regularly showed a 

 slight increase. 



While, then, normal animals show after injection of adrenalin a high- 

 grade hyperglobulia, in the production of which there is surely concerned, 



