Disappearance Rates of Endogenous Luteinizing Hormone and Chorionic Gonadotropin in Man

Abstract

Assessment of the rates of disappearance of endogenous LH and HCG from serum following complete surgical hypophysectomy and removal of the placenta was made. The hormone levels were measured by a specific radioimmunoassay. The disappearance rates for both LH and HCG appear to follow a double exponential curve although there may be a possible additional exponential. The initial disappearance involves a fast process (t½ about 21 min for LH, t½ about 11 hr for HCG) followed by a slower process of disappearance (t½ about 235 min for LH, t½ about 23 hr for HCG), which probably reflects the distribution of these hormones in at least 2 compartments.