title: Mechanism of prolactin action on the dissociation of prolactin from rabbit mammary gland receptor.
abstract: In order to elucidate the action of prolactin (PRL) on the dissociation of PRL from the receptor, Triton-solubilized and concanavalin A-purified rabbit mammary gland PRL receptor was immobilized onto a nitrocellulose membrane, and the dissociation of PRL was determined in the presence of PRL. PRL accelerated the dissociation of PRL in a concentration dependent manner for the first 3 h of incubation. The effects of PRL on dissociation were independent of the occupancy of PRL at the zero-time dissociation. In particular, PRL-dependency was influenced by the PRL-binding capacity of the membrane. The dissociation reaction was PRL-independent in the low-binding capacity membrane, indicating that PRL itself had no accelerating actions. With greater binding capacity, the dissociation reaction was seen to become PRL-dependent. It was concluded that PRL accelerated the dissociation of PRL through the formation of PRL-receptor complex when the receptor was located closely to the neighboring receptors.
authors.affiliation: Department of Animal Breeding, Faculty of Agriculture, University of Tokyo, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Etoh
authors.forename: S
authors.initials: S
authors.lastname: Sakai
mesh_terms: D000818:Animals; D001665:Binding Sites; D005260:Female; D013006:Growth Hormone / Q000502:physiology; D007986:Luteinizing Hormone / Q000502:physiology; D008321:Mammary Glands, Animal / Q000378:metabolism*; D011388:Prolactin / Q000502:physiology*; D011817:Rabbits; D011981:Receptors, Prolactin / Q000378:metabolism*; D013972:Thyrotropin / Q000502:physiology
chemical_list: D011981:Receptors, Prolactin; D011388:Prolactin; D007986:Luteinizing Hormone; D013972:Thyrotropin; D013006:Growth Hormone