THE PITUITARY AND THE THYROID 



to Aron (1933) and Doderlein (1933), large doses of the hor- 

 mone, administered to the mother or fetus, stimulate the 

 fetal thyroid. 



Physiological evidence of thyroid stimulation by anterior- 

 lobe extract has been obtained by recognizing effects pre- 

 sumably produced more or less specifically by the thyroid 

 hormone. The body-weight falls or tends to fall in the young 

 guinea pig although injections are made during a period of 

 rapid growth. Hageman and McCordock (1932) reported 

 that anterior-lobe extract caused an increase in the heart- 

 rate and in the reflex response to an acoustic stimulus; fur- 

 thermore, in thyroidectomized guinea pigs the extract did not 

 produce these effects. Loeb and Friedman (1932) stated that 

 exophthalmos'^ could be observed in guinea pigs after the in- 

 jection of anterior-lobe extract. Grab (1932) injected ante- 

 rior-lobe extract into both dogs and cats; as a result, the blood 

 and serum of the treated animals contained an increased 

 amount of thyroid hormone demonstrated by the protection 

 of mice against acetonitril and by the acceleration of tadpole 

 metamorphosis. Pighini (1933) found that the serum of 

 treated dogs (but not of normal dogs) accelerated the meta- 

 morphosis of tadpoles, but he could detect no differences in the 

 amount of thyroid hormone in the thyroid. Grab believed 

 that the treated animal's thyroid might contain less thyroid 

 hormone but that this change could be obscured by the new 

 formation of thyroid hormone. If the experiments of Oehme, 

 Paal, and Kleine (1932) were sufficiently accurate quantita- 

 tively, they seemed to indicate that the mouse thyroid can 

 only discharge the equivalent of less than 1.5 7 of thyroxin. 



'5 Exophthalmos can be produced in the thyroidectomized guinea pig by either 

 acetonitril or anterior-lobe extract (of Armour's powder) according to Marine and 

 Rosen (1933). They believed that exophthalmos is produced by a secretion of the 

 anterior pituitary, particularly if there is a thyroid deficiency. They performed no 

 experiments with hypophysectomized guinea pigs to support their theory that the 

 exophthalmos following the administration of acetonitril is the result of a direct 

 or indirect stimulation of the pituitary. 



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