The Effect of a Growth-promoting Extract of the Anterior Pituitary on the Early Growth of the Albino Rat

Castrate male albino rats were injected with a growth-promoting extract of bovine anterior pituitary from the 21st day of life (day of castration) to the 56th day (average for group) at which time the difference in weight between the pituitary-injected animals and controls was first clearly discernible. In comparison to controls the pituitary-injected animals at this stage showed: (1) a decrease in the weight of the pituitary gland; (2) an increase in nose-anus length; (3) an increase in the weight of heart, lungs, liver, and kidneys which is shown to be of the nature of a splanchnomegaly; (4) an increase in the weight of the blood removed; (5) an increase in the water content of the skin and the kidneys; (6) a tendency toward an increase in weight of the carcass. The significance of these findings is discussed.