SIGNIFICANCE OF THE SUPRARENAL GLANDS 167 



important question, whether the thyroid influences or can influence the 

 rate of output of epinephrin. But Kuriyama(a) (b) has been unable to 

 detect any definite effect produced by thyroid feeding upon the epinephrin 

 store when the ordinary variations in its amount are taken into account. 

 Gley(a)(1914) arrived at a similar negative result as to the effect of 

 thyroidectomy and of removal of the pancreas (c) (1915). 



There is, however, no reason to doubt that when certain conditions 

 as to dosage and duration of feeding are observed, the suprarenals may 

 hypertrophy (and the epinephrin store increase) as Herring has main- 

 tained, in confirmation of the observations of E. R. and R. G. Hoskins(o-). 

 But there is nothing specific about this increase in size of the suprarenals 

 since similar hypertrophy is found in other organs, including the pancreas 

 (E. R. Hoskins, Kojima) after thyroid feeding. The risk of deducing 

 a special physiological relationship between the thyroid and the supra- 

 renals merely because hypertrophy of the suprarenals has followed thyroid 

 feeding is illustrated by the fact that removal of the thyroids may also be 

 associated with suprarenal hypertrophy (Gley(a), Carlson, Stewart and 

 Rogoff (z) ). These glands, indeed, seem to vary much in size, like the thy- 

 roid, and under many physiological and pathological conditions. Their 

 hypertrophy in pregnancy (Guiyesse(fr), Watrin(a), et al.) and still more 

 during lactation (Verdozzi(a,)) seems to be a normal physiological event, 

 but its significance is unknown. C. A. Stewart (b) observed a progressive 

 increase in the size of the suprarenals in young rats, underfed for long 

 periods. Jackson (&) has also described changes in the suprarenals of rats 

 during inanition. McCarrison(c) saw enlargement of the suprarenals 

 associated with inanition and also with a scorbutic diet, and Vincent and 

 Hollenberg have confirmed his findings. Many infections and intoxica- 

 tions are accompanied by suprarenal enlargement (Langlois(c), Porak (&), 

 et al.), although enlargement due to edema (and congestion) has not always 

 been discriminated from true hypertrophy. Mulon and Porak found that 

 in animals employed for the production of antibodies of various kinds the 

 cortex was hypertrophied. Porak says that the largest suprarenals seen by 

 him were in rabbits repeatedly injected with sheep's erythrocytes for the 

 production of anti-sheep serum for the Wassermann test in the Paris 

 municipal laboratory. 



Statements in the literature to the effect that extracts of thyroid, pan- 

 creas, liver, testes, kidneys, and of other organs increase the output of 

 epinephrin (Gley and Quinquaud(a) et al.), in so far as they are not based 

 ipon a faulty technic, are simply due to a failure to distinguish between 

 an increased concentration of epinephrin in the blood coming from the 

 suprarenals and an increased output of epinephrin per unit of time. It is 

 well known that such tissue extracts cause a fall of blood-pressure and, 

 lerefore, a slowing of the blood flow. The concentration of epinephrin 



