Biomaterial Database

Studies of TRH-induced prolactin secretion and its inhibition by dopamine, using ovine pituitary cells. 1984

K P Ray, and M Wallis

Prolactin secretion from ovine pituitary cell cultures was stimulated by thyrotropin-releasing hormone (TRH) (10(-10)-10(-7) M) with a half-maximal effect at approximately 2.5 X 10(-9) M. A maximally effective concentration of TRH produced a peak secretory response, 5-10-fold stimulation over basal release, within 15 min. Dopamine (10(-10)-10(-7) M) but not somatostatin caused a dose-related inhibition of TRH (10(-8) M) stimulated prolactin release. Both dopamine (10(-7) M) and somatostatin (10(-7) M) inhibited basal secretion from the cells. TRH did not significantly increase pituitary cell cyclic AMP levels under any of the conditions tested. Stimulation of prolactin secretion by TRH was not prevented when Ca2+ was omitted from the incubation medium. Dopamine inhibited secretion induced by TRH under low Ca2+ conditions. Our results are consistent with a hypothesis that TRH may stimulate prolactin secretion via release of intracellular Ca2+ rather than increased cellular Ca2+ uptake, and imply that dopamine inhibition involves a lowering of intracellular Ca2+ levels.

UI	MeSH Term	Description	Entries
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
D011388	Prolactin	A lactogenic hormone secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). It is a polypeptide of approximately 23 kD. Besides its major action on lactation, in some species prolactin exerts effects on reproduction, maternal behavior, fat metabolism, immunomodulation and osmoregulation. Prolactin receptors are present in the mammary gland, hypothalamus, liver, ovary, testis, and prostate.	Lactogenic Hormone, Pituitary,Mammotropic Hormone, Pituitary,Mammotropin,PRL (Prolactin),Hormone, Pituitary Lactogenic,Hormone, Pituitary Mammotropic,Pituitary Lactogenic Hormone,Pituitary Mammotropic Hormone
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
D004298	Dopamine	One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.	Hydroxytyramine,3,4-Dihydroxyphenethylamine,4-(2-Aminoethyl)-1,2-benzenediol,Dopamine Hydrochloride,Intropin,3,4 Dihydroxyphenethylamine,Hydrochloride, Dopamine
D005260	Female		Females
D000242	Cyclic AMP	An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.	Adenosine Cyclic 3',5'-Monophosphate,Adenosine Cyclic 3,5 Monophosphate,Adenosine Cyclic Monophosphate,Adenosine Cyclic-3',5'-Monophosphate,Cyclic AMP, (R)-Isomer,Cyclic AMP, Disodium Salt,Cyclic AMP, Monoammonium Salt,Cyclic AMP, Monopotassium Salt,Cyclic AMP, Monosodium Salt,Cyclic AMP, Sodium Salt,3',5'-Monophosphate, Adenosine Cyclic,AMP, Cyclic,Adenosine Cyclic 3',5' Monophosphate,Cyclic 3',5'-Monophosphate, Adenosine,Cyclic Monophosphate, Adenosine,Cyclic-3',5'-Monophosphate, Adenosine,Monophosphate, Adenosine Cyclic
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
D012756	Sheep	Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.	Ovis,Sheep, Dall,Dall Sheep,Ovis dalli
D013004	Somatostatin	A 14-amino acid peptide named for its ability to inhibit pituitary GROWTH HORMONE release, also called somatotropin release-inhibiting factor. It is expressed in the central and peripheral nervous systems, the gut, and other organs. SRIF can also inhibit the release of THYROID-STIMULATING HORMONE; PROLACTIN; INSULIN; and GLUCAGON besides acting as a neurotransmitter and neuromodulator. In a number of species including humans, there is an additional form of somatostatin, SRIF-28 with a 14-amino acid extension at the N-terminal.	Cyclic Somatostatin,Somatostatin-14,Somatotropin Release-Inhibiting Hormone,SRIH-14,Somatofalk,Somatostatin, Cyclic,Somatotropin Release-Inhibiting Factor,Stilamin,Somatostatin 14,Somatotropin Release Inhibiting Factor,Somatotropin Release Inhibiting Hormone
D013973	Thyrotropin-Releasing Hormone	A tripeptide that stimulates the release of THYROTROPIN and PROLACTIN. It is synthesized by the neurons in the PARAVENTRICULAR NUCLEUS of the HYPOTHALAMUS. After being released into the pituitary portal circulation, TRH (was called TRF) stimulates the release of TSH and PRL from the ANTERIOR PITUITARY GLAND.	Protirelin,Thyroliberin,Abbott-38579,Antepan,Proterelin Tartrate,Proterelin Tartrate Hydrate,Protirelin Tartrate (1:1),Relefact TRH,Stimu-TSH,TRH Ferring,TRH Prem,Thypinone,Thyroliberin TRH Merck,Thyrotropin-Releasing Factor,Thyrotropin-Releasing Hormone Tartrate,Abbott 38579,Abbott38579,Hydrate, Proterelin Tartrate,Prem, TRH,Stimu TSH,StimuTSH,TRH, Relefact,Tartrate Hydrate, Proterelin,Thyrotropin Releasing Factor,Thyrotropin Releasing Hormone,Thyrotropin Releasing Hormone Tartrate