Presence and characterization of prolactin receptors in human benign breast tumours.

Prolactin receptors have been determined in 64 benign breast tumours. A specific binding of 0.5% or more (with a range of 0.5-3.3%) was found in 34.4% of the cases and was considered prolactin-receptor-positive. The binding was found to be specific only for lactogenic hormones. By Scatchard analysis the dissociation constant was 2.55 X 10(-10) mol/l and the binding capacity was 4.6 fmol/mg protein.