title: Comparative measurement of the lactogenic activity of ovine placental lactogen in rabbit and ewe mammary gland.
abstract: Ovine placental lactogen is known to bind to prolactin receptors and to initiate milk synthesis in the rabbit mammary gland. However, this hormone exhibited a very low capacity of competing with 125I-labeled human growth hormone for the binding to membranes extracted from ewe mammary gland. Ovine placental lactogen was very efficient in provoking the accumulation of beta-casein mRNA in rabbit mammary explants but was much less active on ewe mammary explants. These data indicate that the placental hormone is not a potent lactogen in the homologous species and that its role in the control of mammary gland development and activity may have been previously overestimated.
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D002364:Caseins / Q000096:biosynthesis; D005260:Female; D013006:Growth Hormone / Q000378:metabolism; D006801:Humans; D007774:Lactation; D008321:Mammary Glands, Animal / Q000378:metabolism*; D008566:Membranes / Q000378:metabolism; D010928:Placental Lactogen / Q000032:analysis* / Q000378:metabolism / Q000502:physiology; D011247:Pregnancy; D011817:Rabbits; D011956:Receptors, Cell Surface / Q000032:analysis*; D011981:Receptors, Prolactin; D012756:Sheep
chemical_list: D002364:Caseins; D011956:Receptors, Cell Surface; D011981:Receptors, Prolactin; D013006:Growth Hormone; D010928:Placental Lactogen