Progestin receptors in dispersed rat anterior pituitary cells: enriched binding in lactotrope fractions.
Cytosolic progesterone and R5020 binding activities were demonstrated in Pronase-dispersed anterior pituitary cells from estrogen-primed ovariectomized and adrenalectomized rats. Pronase-dispersed pituitary cells were also separated into six cellular fractions on the basis of size and density by sedimentation velocity at unit gravity in a BSA gradient. Fractions enriched in lactotropes or gonadotropes were identified by the cellular contents of radioimmunoassayable prolactin and LH, respectively. Cytosolic progestin receptors appeared to be predominantly associated with lactotrope-rich fractions. Since there was some cross-over between the LH and prolactin enriched fractions, progestin receptors may also be associated with a subpopulation of gonadotropes, as well.
D000818:Animals; D002369:Castration; D002469:Cell Separation; D005260:Female; D007986:Luteinizing Hormone / Q000378:metabolism; D010903:Pituitary Gland, Anterior / Q000166:cytology / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism; D011397:Promegestone / Q000378:metabolism; D051381:Rats; D011980:Receptors, Progesterone / Q000378:metabolism*
D011980:Receptors, Progesterone; D011374:Progesterone; D011388:Prolactin; D007986:Luteinizing Hormone; D011397:Promegestone