Human placental lactogen: Further evidence of placental mimicry of pituitary function

Abstract

THE PRESENCE OF one or more proteins in human placental extracts which would stimulate crop sac growth in the pigeon was first demonstrated by Higashi in collaboration with Ito.“-* Somatotropic activity of extracts of the human placenta was also demonstrated earlier by Fukushima.” This note recounts the efforts to identify and purify human placental lactogen (HPL, human chorionic somatomammotropin~ in our laboratory at the Boston Lying-In Hospital and in the Department of Obstetrics and Gynecology, Harvard Medical School. These endeavors are presented as they summarize the importance of research leadership of the chairman of a clinical department, the importance of early financial support for junior investigator, the provision of time for them to carry out such research, the availability of newer techniques at a criticai time in the development of research project, devotion of one’s research technicians, the close proximity of numerous colleagues in allied fields to help in the development of research techniques, and previous preand post-doctoral training in research meth~ology, I had received preand post-doctoral training supported by the Josiah Macy, Jr., Foundation at the Harvard Medical School, Department of Physiology, laboratory of Ernst Knob& where the species specificity of human pituitary growth hormone was discovered, Because of this background, Duncan E. Reid suggested that I embark on a search for the growth hormone-like factor