210 Thyroid and Adrenal 
mg., the minimum 1.72 mg. It will be seen that the epinephrine 
content of the adrenal shows some variation according to both 
the animal species and the individual. 
| As the thyroid hormone is considered to stimulate the sympa- 
thetic nervous system, an excess of it in the body may stimulate 
the activity of the adrenal. But this may not necessarily be ac- 
companied by a higher content of the epinephrine in the gland. 
The excess of epinephrine may immediately be transported into 
the circulation, its concentration in the gland being kept as 
usual. It is also possible that the epinephrine produced in the 
gland, no matter what the amount may be, is quickly expelled 
by the abnormal nerve stimulation and consequently the lower 
concentration soon manifests itself. Quinquaud® reported that 
the epinephrine content of the adrenal was decreased after pigéire. 
Confirming the results of Elliott, Stewart and Rogoff’ reported 
that diminution of the stock of epinephrine in the adrenal, through 
electrical stimulation of the splanchnics, was not easy to demon- 
strate, despite the fact that the liberation of epinephrine into the 
blood was notably increased by the stimulation. Only after a 
stimulation, repeated at intervals for a long time, could a distinct 
depletion of the epinephrine content be observed. ‘The results in 
Table II show that the epinephrine content of the adrenal was 
practically not changed by thyroid feeding (a small dose per day 
for a long time, and a large dose per day for a short time), neither 
absolutely nor relatively, the individual or physiological variations 
being kept in mind. Neither do the absolute and relative weights | 
of the adrenals show any noteworthy difference from those of the 
control animals. According to Donaldson’s tables,* the weight 
of the adrenals of albino rats is 45.6 mg. (average of both sexes) 
for 200 gm. of body weight, and 48.2 mg. (average of both sexes) 
for 215 gm. of body weight. In his chart it may be seen that 
there exists a widely ranging variation. In Herring’s report, 
‘the epinephrine content of the adrenals of the thyroid-fed ani- 
mals was increased absolutely but decreased when it was calcu- 
lated per gm. of the adrenal. The weight of the fresh adrenals 
> Quinquaud, A., Relations entre la piqdre diabétique et la sécrétion 
d’adrénaline, Paris, 1915. 
§ Elliott, TP. R:, J. Physiol., 1912) xliv, 374. 
* Stewart, G. N., and Rogoff, J. M., J. Hap. Med., 1916, xxiv, 709. 
8 Donaldson, H. H., The Rat, Philadelphia, 1915, 100, 137. 
