Some Hormones Involved in Elaboration or Activation of the Mammary Spreading Factor.

Abstract

Injns. of varying amts. of estradiol benzoate, progesterone, testosterone and an anterior pituitary extract separately; and estradiol benzoate and progesterone in combinations into castrated albino rats resulted in the elaboration or activation of the mammary spreading factor. Injns. of estradiol benzoate into castrate-adrenalectomized albino rats resulted in little or no elaboration or activation of the spreading factor while results of other injected materials was the same in castrate-adrenalectomized animals as in the castrate animals. The greatest amount of spreading factor was produced with a combination of 1 [mu]g. estradiol benzoate and 5 mg. progesterone. It is suggested that hormones regulating mammary gland growth are responsible for elaboration or activation of the spreading factor.