THE SYMPATHETIC SYSTEM 59 



1895 showed that the intra venous injection of thyroid 

 extract caused a drop in the blood pressure. Heinatz 

 noticed the marked acceleration of the heart and pulse 

 following its injection. 



All the observations concerning the action of thyroid 

 extract agree that there is a loss of weight following the 

 injection of thyroid, even when the food is abundant 

 and at the same time, there is an increase in diuresis, and 

 of elimination of urea and nitrogen. 



III. EXPERIMENTAL HYPERTHYROIDISM. 



Ballet and Enriquez by having animals absorb large 

 doses of thyroid were able to observe a syndrome of hyper- 

 thyroidism characterized by tachycardia, fever, nervous 

 disturbances (restlessness and tremor), followed by loss of 

 weight and diarrhea. 



All these physiological and experimental facts allow us 

 to interpret the various syndromes of hypersecretion, and 

 insufficiency observed in man. 



