Properties of LHRH release from a hypothalamic synaptosomal fraction of estrogen-primed ovariectomized rats. 1980

M Tytell, and J H Clark, and E J Peck

The release of luteinizing hormone-releasing hormone (LHRH) from mitochondrial-synaptosomal fractions (P2) of basomedial hypothalamus was examined under various conditions. Less than 3% of the LHRH in P2 suspensions was released under control conditions while the addition of 60 mM KCl or NaCl effected an 8-fold increase in LHRH as measured by radioimmunoassay. Equiosmolar sucrose effected only a 1.8-fold increase in LHRH release. The stimulatory effects of both Na+ and K+ were significantly inhibited by Mn2+ or La3+. Two forms of released LHRH were observed, one soluble and the other particulate. Soluble LHRH release was effected by hypertonic sucrose or 60 mM KCl and was not inhibited by Ca2+ antagonists. The release of particulate LHRH was unaffected by hpertonic sucrose, was stimulated 10-fold by 60 mM KCl, and was abolished with Ca2+ antagonists. These results suggest that the released soluble LHRH results from nonspecific leakage while the release of particulate LHRH reflects a Ca2+-dependent secretory process.

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
D007700 Kinetics The rate dynamics in chemical or physical systems.
D007811 Lanthanum The prototypical element in the rare earth family of metals. It has the atomic symbol La, atomic number 57, and atomic weight 138.91. Lanthanide ion is used in experimental biology as a calcium antagonist; lanthanum oxide improves the optical properties of glass.
D007987 Gonadotropin-Releasing Hormone A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE. GnRH is produced by neurons in the septum PREOPTIC AREA of the HYPOTHALAMUS and released into the pituitary portal blood, leading to stimulation of GONADOTROPHS in the ANTERIOR PITUITARY GLAND. FSH-Releasing Hormone,GnRH,Gonadoliberin,Gonadorelin,LH-FSH Releasing Hormone,LHRH,Luliberin,Luteinizing Hormone-Releasing Hormone,Cystorelin,Dirigestran,Factrel,Gn-RH,Gonadorelin Acetate,Gonadorelin Hydrochloride,Kryptocur,LFRH,LH-RH,LH-Releasing Hormone,LHFSH Releasing Hormone,LHFSHRH,FSH Releasing Hormone,Gonadotropin Releasing Hormone,LH FSH Releasing Hormone,LH Releasing Hormone,Luteinizing Hormone Releasing Hormone,Releasing Hormone, LHFSH
D008345 Manganese A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
D011188 Potassium An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D002118 Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002369 Castration Surgical removal or artificial destruction of gonads. Gonadectomy,Castrations,Gonadectomies
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

Related Publications

M Tytell, and J H Clark, and E J Peck
February 1981, Endocrinologia japonica,
M Tytell, and J H Clark, and E J Peck
January 1979, Brain research bulletin,
M Tytell, and J H Clark, and E J Peck
January 2006, Neuro endocrinology letters,
M Tytell, and J H Clark, and E J Peck
November 1988, Pharmacology, biochemistry, and behavior,
M Tytell, and J H Clark, and E J Peck
November 1997, Journal of neuroendocrinology,
M Tytell, and J H Clark, and E J Peck
August 2002, Brain research,
Copied contents to your clipboard!