EFFECT OF THYEOIDECTOMY ON NITROGENOUS METABOLISM. 477 



after an interval, the temperature being maintained meanwhile 

 by diminished loss from the surface by vaso-motor constriction 

 of the arteries. It is precisely these vaso-motor changes 

 which are at fault in myxoedema; and in order to maintain 

 the normal temperature, the production of COg is increased 

 at once. 



The amount of urea excreted by patients with myxoedema is 

 generally diminished, but as no record has been kept of the 

 nitrogenous food, the observation is useless. 



Many observers (3) have investigated the metabolism during 

 thyroid feeding, and have usually obtained a distinct increase 

 in the nitrogenous output. Georgiewsky (4) found glycosuria 

 and increase of urea, confirmed by Bettmann (5), who considers 

 it 'alimentary glycosuria.' Eichter (6) obtained a negative 

 result in man. Bleibtreu and Wendelstadt (7), and Eoos (8) 

 obtained a marked increase in excreted nitro2;en. Schondorff 

 (9) obtained an increased excretion of nitrogen during the first 

 eight days in dogs ; after that, nitrogenous equilibrium is 

 mamtained, while the body-fat is greatly diminished in 

 amount. The NaCl and phosphates were also increased. 

 There is no after effect, so that when the thyroid feeding is 

 stopped, the nitrogen output sinks at once to normal ; more- 

 over, renewed feeding will now produce no effect upon the 

 nitrogenous metabolism, the animal having become used 

 to it. 



Ver Eecke (10), working with dogs, cats, rabbits and guinea- 

 pigs, found that thyroidectomy produced a diminution in the 

 amount of urine, which is only temporary when the operation 

 is partial. Feeding produces diuresis. The nitrogen output 

 sinks the more gland is removed, but as the remainder 

 hypertrophies, the output may increase beyond the normal. 

 The phosphorus output is increased in thyroidectomy and 

 diminished in thyroid feeding. The sodium output varies 

 with the diuresis. 



Andersson and Bergmann (1 1), using the Tigerstedt-Sonden 

 apparatus for men, confirmed these results both as to thyroid 

 feeding and the exhibition of iodo-thyrin. 



