Human neurophysins during pregnancy, puerperium and menstrual cycles.

Abstract

To clarify the hypothalamo-posterior pituitary function during pregnancy, puerperium and menstrual cycle, investigations were performed to determine the levels of serum neurophysins by specific radioimmunoassays. Sera from 75 women during normal pregnancy, 17 during postpartum and 49 during the normal menstrual cycle were assayed for Estrogen Stimulated Neuro-physin (ESN) and Nicotine Stimulated Neurophysin (NSN). ESN, associated with oxytocin increased during pregnancy and the values decreased to non-pregnant levels after parturition. During menstrual cycle ESN showed three peaks. In contrast, NSN, associated with vasopressin was little changed throughout the menstrual cycle, pregnancy and the puerperium. In this study two neurophysins changed independently, suggesting the hypothesis of “one hormone-one neurophysin.” The data also would indicate the availability of measurement of these two substances on the study of the function of human neurosecretory system.