THE EFFECTS OF COMBINATIONS OF KI WITH ACID ANTERIOR PITUITARY EXTRACTS, KI WITH ARMOUR'S ANTERIOR PITUITARY, AND KI WITH THYROID SUBSTANCE UPON BASAL METABOLISM IN GUINEA PIGS

¹ From the Department of Pathology, Washington University School of Medicine, St. Louis, Missouri

1. Acid extracts of anterior pituitary of cattle produce in guinea pigs a marked rise in basal metabolism. Simultaneous administration of KI markedly diminishes or even prevents this rise.

2. Armour's anterior pituitary preparations and thyroid substance also cause a marked rise in basal metabolism, but this rise is not only not diminished by simultaneous administration of KI, but may be slightly increased by it.

3. Simultaneous administration of KI in guinea pigs in which our anterior pituitary preparation caused a rise in metabolism diminishes the loss in weight caused by anterior pituitary injections alone. On the other hand, administration of XI in combination with Armour's anterior pituitary or with thyroid substance does not diminish the loss of weight caused by the former substances but may perhaps increase it, at least in combination with Armour's preparation.

4. There is a correspondence between the structural changes produced by the addition of KI to our preparations of anterior pituitary and its effects on basal metabolism. It has, therefore, been possible to predict on the basis of the structural changes the effects of the various combinations used by us on basal metabolism.