APPARENT HETEROGENEITY OF SERUM CHORIONIC SOMATOMAMMOTROPHIN ON GEL FILTRATION

Abstract

ABSTRACT Pregnancy sera, cord sera and placental homogenates were applied to Sephadex G-100 and the human chorionic somatomammotrophin (HCS) concentrations in the eluates were estimated by radioimmunoassay. Two HCS peaks were obtained when maternal serum or placental homogenates were used. The minor component, representing 0.5% – 3.0% of the total HCS recovered, appeared to have a molecular weight of about 45 000 and the major component a molecular weight of 21 500. The two HCS components were found under a variety of conditions and it appears that a small proportion of serum HCS may be in a dimeric form.