PARS GLANDULARIS AND METABOLISM 



ectomy; in other words, the removal of the thyroid is fol- 

 lowed by enlargement of the liver. The experimentally en- 

 larged liver contains about twice as high a concentration of 

 lipoids (10.4 per cent) as the normal liver (5.1 per cent), but 

 if, in addition to thyroidectomy, anterior pituitary extract 

 be injected into the duck, there is further hypertrophy and 

 the concentration of lipoid rises to 38.6 per cent (Benoit, 

 1936). The observations of Best and Campbell (1936) were 

 made in rats. Large doses of anterior pituitary extract were 

 followed by the deposition of large amounts of fat (total fatty 

 acids together with unsaponifiable material) in the liver. As- 

 sociated changes in fasting rats were a decrease in the fat of 

 other parts of the body and an increased excretion of acetone 

 bodies. The accumulation of fat in the liver as a result of the 

 injection of anterior pituitary extract is prevented by adren- 

 alectomy but not by demedullation of the adrenals (Fry, 

 1937). Likewise, MacKay and Barnes (1937) showed that 

 adrenalectomy prevents the deposition of fat in the liver, 

 caused either by anterior pituitary extract or by fasting. 



Pancreatectomy is ordinarily followed by an accumulation 

 of lipoids in the liver of animals such as the dog. This change 

 is not prevented if hypophysectomy also is performed (Chai- 

 koff and others, 1936). 



The relation of what Anselmino and Hoffmann term the 

 "fat-metabolism hormone" to the accumulation of lipoids in 

 the liver is not clear. Pituitary extract may cause, under 

 proper experimental conditions, an accumulation of acetone 

 bodies in the blood and an increased excretion of the bodies 

 in the urine. An extract with such effects is what Anselmino 

 and Hoffmann have called the "fat-metabolism hormone." 

 Its other effects come up for discussion shortly. Although 

 Anselmino, Hoffmann, and Rhoden (1936) state that extract 

 with the previously described properties is identical with the 

 active substance present in the extracts of Best and Camp- 

 bell and causes an increase of about 50 per cent in the con- 

 centration of ether-soluble substances in the liver dried at 



[229I 



