Biomaterial Database

Direct pituitary effects of estradiol and progesterone on luteinizing hormone release, stores, and subunit messenger ribonucleic acids. 1991

R L Girmus, and M E Wise

Department of Animal Science, University of Arizona, Tucson 85721.

To determine the direct, chronic actions of progesterone (P4) and estrogen (estradiol, E2) on anterior pituitary synthesis and release of LH, 24 western range ewes underwent hypothalamic-pituitary disconnection (HPD) and ovariectomy (OVX) during the breeding season and were pulsed with exogenous GnRH with or without steroid replacement. Sequential blood samples were collected before infusion of GnRH and on Days 7 and 14 of GnRH infusion. Silastic capsules of P4 and/or E2 were implanted s.c. on Day 7 and remained in place throughout the experiment. Control ewes received only GnRH infusion. Blood sampling was centered around three exogenous GnRH pulses. After the final blood sampling, pituitaries were collected and stored at -70 degrees C. Concentrations of LH in serum and pituitaries were determined by RIA. Relative concentrations of LH subunit mRNAs were determined by Fast Blot analysis. Simultaneous implantation of P4 and E2 lowered LH pulse amplitude 70% and mean serum levels 30% compared with controls. Neither steroid alone affected LH release. E2 alone or in combination with P4 lowered LH-beta subunit mRNA concentrations 40% compared with controls while alpha-subunit levels were unchanged. Only E2 alone altered the pituitary content of LH, causing a 60% decrease. We conclude that the combination of P4 and E2 is necessary for inhibition of GnRH-stimulated LH secretion. E2 inhibits GnRH-stimulated LH-beta subunit mRNA concentrations but does not affect alpha-subunit mRNA concentrations. The control of pituitary LH content by P4 and E2 is the result of changes in both LH-beta subunit mRNA concentrations and LH secretion.

UI	MeSH Term	Description	Entries
D007031	Hypothalamus	Ventral part of the DIENCEPHALON extending from the region of the OPTIC CHIASM to the caudal border of the MAMMILLARY BODIES and forming the inferior and lateral walls of the THIRD VENTRICLE.	Lamina Terminalis,Preoptico-Hypothalamic Area,Area, Preoptico-Hypothalamic,Areas, Preoptico-Hypothalamic,Preoptico Hypothalamic Area,Preoptico-Hypothalamic Areas
D007986	Luteinizing Hormone	A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.	ICSH (Interstitial Cell Stimulating Hormone),Interstitial Cell-Stimulating Hormone,LH (Luteinizing Hormone),Lutropin,Luteoziman,Luteozyman,Hormone, Interstitial Cell-Stimulating,Hormone, Luteinizing,Interstitial Cell Stimulating Hormone
D010052	Ovariectomy	The surgical removal of one or both ovaries.	Castration, Female,Oophorectomy,Bilateral Ovariectomy,Bilateral Ovariectomies,Castrations, Female,Female Castration,Female Castrations,Oophorectomies,Ovariectomies,Ovariectomies, Bilateral,Ovariectomy, Bilateral
D010053	Ovary	The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.	Ovaries
D010902	Pituitary Gland	A small, unpaired gland situated in the SELLA TURCICA. It is connected to the HYPOTHALAMUS by a short stalk which is called the INFUNDIBULUM.	Hypophysis,Hypothalamus, Infundibular,Infundibular Stalk,Infundibular Stem,Infundibulum (Hypophysis),Infundibulum, Hypophyseal,Pituitary Stalk,Hypophyseal Infundibulum,Hypophyseal Stalk,Hypophysis Cerebri,Infundibulum,Cerebri, Hypophysis,Cerebrus, Hypophysis,Gland, Pituitary,Glands, Pituitary,Hypophyseal Stalks,Hypophyses,Hypophysis Cerebrus,Infundibular Hypothalamus,Infundibular Stalks,Infundibulums,Pituitary Glands,Pituitary Stalks,Stalk, Hypophyseal,Stalk, Infundibular,Stalks, Hypophyseal,Stalks, Infundibular
D011374	Progesterone	The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.	Pregnenedione,Progesterone, (13 alpha,17 alpha)-(+-)-Isomer,Progesterone, (17 alpha)-Isomer,Progesterone, (9 beta,10 alpha)-Isomer
D004958	Estradiol	The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.	17 beta-Estradiol,Estradiol-17 beta,Oestradiol,17 beta-Oestradiol,Aerodiol,Delestrogen,Estrace,Estraderm TTS,Estradiol Anhydrous,Estradiol Hemihydrate,Estradiol Hemihydrate, (17 alpha)-Isomer,Estradiol Monohydrate,Estradiol Valerate,Estradiol Valeriante,Estradiol, (+-)-Isomer,Estradiol, (-)-Isomer,Estradiol, (16 alpha,17 alpha)-Isomer,Estradiol, (16 alpha,17 beta)-Isomer,Estradiol, (17-alpha)-Isomer,Estradiol, (8 alpha,17 beta)-(+-)-Isomer,Estradiol, (8 alpha,17 beta)-Isomer,Estradiol, (9 beta,17 alpha)-Isomer,Estradiol, (9 beta,17 beta)-Isomer,Estradiol, Monosodium Salt,Estradiol, Sodium Salt,Estradiol-17 alpha,Estradiol-17beta,Ovocyclin,Progynon-Depot,Progynova,Vivelle,17 beta Estradiol,17 beta Oestradiol,Estradiol 17 alpha,Estradiol 17 beta,Estradiol 17beta,Progynon Depot
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012333	RNA, Messenger	RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.	Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated