Chorionic Gonadotrophin, ACTH, and the Adrenal-Hyaluronidase Relationship *

It has been shown that either adrenocorticotrophic hormone (ACTH) or the 11-oxygenated adrenal cortical steroids inhibit the hyaluronidaseenhanced spreading phenomenon in the rabbit and in the mouse.q 8 In view of the favorable influence of pregnancy on certain of the collagen diseases, it was of interest to determine whether chorionic gonadotrophin had any influence on this phenomenon. This was found to be the case, but in the course of these investigations it became apparent that the inhibition produced by this agent was probably due, not to the gonad-stimulating principle, but to a contaminant which exhibited many of the properties previously associated with ACTH from pituitary tissue. While this work was in progress, Jailer and Knowlton' published a paper in which the presence of ACTH-like activity in extracts of placenta was indicated. The present study is to be regarded as of a preliminary nature since many points concerning the nature of the adrenal cortical stimulating principle remain to be clarified.