Biomaterial Database

Noradrenergic control of central oxytocin release during lactation in rats. 1998

S L Bealer, and W R Crowley

Department of Physiology, University of Tennessee, Memphis 38163, USA.

Noradrenergic systems regulate the systemic release of oxytocin (OT) in lactating rats. However, a role for norepinephrine (NE) in release of OT within the magnocellular nuclei during suckling has not been established. These studies were designed to determine 1) if suckling induces NE release in the supraoptic (SON) and paraventricular (PVN) nuclei of conscious rats and 2) the role of NE in the central, intranuclear release of OT within these nuclei. Female Holtzman rats were implanted with microdialysis probes adjacent to the PVN or SON on lactation days 8-12. The following day, the pups were isolated from the dams for 4 h. Microdialysis probes were perfused with artificial cerebrospinal fluid (ACSF) or with ACSF containing an alpha- or a beta-adrenergic receptor antagonist. Dialysate was collected before, during, and after suckling and analyzed for NE or OT. In an additional experiment, an alpha- or beta-adrenergic agonist was administered via the microdialysis probes into the PVN in nonsuckled, lactating rats. Extracellular NE increased in the PVN during suckling but was not detectable in the SON. OT concentrations in dialysates from the PVN and SON significantly increased during suckling. Blockade of either alpha-(in both PVN and SON) or beta- (PVN) adrenergic receptors prevented the suckling-induced increase in central OT release. OT release was increased in nonsuckled, lactating rats by central application of either an alpha- or beta-adrenergic agonist. These data demonstrate that intranuclear NE release is increased in the PVN by suckling and that subsequent stimulation of both alpha- and beta-noradrenergic receptors mediates intranuclear OT release.

UI	MeSH Term	Description	Entries
D007774	Lactation	The processes of milk secretion by the maternal MAMMARY GLANDS after PARTURITION. The proliferation of the mammary glandular tissue, milk synthesis, and milk expulsion or let down are regulated by the interactions of several hormones including ESTRADIOL; PROGESTERONE; PROLACTIN; and OXYTOCIN.	Lactation, Prolonged,Milk Secretion,Lactations, Prolonged,Milk Secretions,Prolonged Lactation,Prolonged Lactations
D009638	Norepinephrine	Precursor of epinephrine that is secreted by the ADRENAL MEDULLA and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the LOCUS CERULEUS. It is also found in plants and is used pharmacologically as a sympathomimetic.	Levarterenol,Levonorepinephrine,Noradrenaline,Arterenol,Levonor,Levophed,Levophed Bitartrate,Noradrenaline Bitartrate,Noradrénaline tartrate renaudin,Norepinephrin d-Tartrate (1:1),Norepinephrine Bitartrate,Norepinephrine Hydrochloride,Norepinephrine Hydrochloride, (+)-Isomer,Norepinephrine Hydrochloride, (+,-)-Isomer,Norepinephrine d-Tartrate (1:1),Norepinephrine l-Tartrate (1:1),Norepinephrine l-Tartrate (1:1), (+,-)-Isomer,Norepinephrine l-Tartrate (1:1), Monohydrate,Norepinephrine l-Tartrate (1:1), Monohydrate, (+)-Isomer,Norepinephrine l-Tartrate (1:2),Norepinephrine l-Tartrate, (+)-Isomer,Norepinephrine, (+)-Isomer,Norepinephrine, (+,-)-Isomer
D010121	Oxytocin	A nonapeptide hormone released from the neurohypophysis (PITUITARY GLAND, POSTERIOR). It differs from VASOPRESSIN by two amino acids at residues 3 and 8. Oxytocin acts on SMOOTH MUSCLE CELLS, such as causing UTERINE CONTRACTIONS and MILK EJECTION.	Ocytocin,Pitocin,Syntocinon
D010286	Paraventricular Hypothalamic Nucleus	Nucleus in the anterior part of the HYPOTHALAMUS.	Hypothalamic Paraventricular Nucleus,Paraventricular Nucleus,Hypothalamic Nucleus, Paraventricular,Nucleus, Hypothalamic Paraventricular,Nucleus, Paraventricular,Nucleus, Paraventricular Hypothalamic,Paraventricular Nucleus, Hypothalamic
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D005260	Female		Females
D000316	Adrenergic alpha-Agonists	Drugs that selectively bind to and activate alpha adrenergic receptors.	Adrenergic alpha-Receptor Agonists,alpha-Adrenergic Receptor Agonists,Adrenergic alpha-Agonist,Adrenergic alpha-Receptor Agonist,Receptor Agonists, Adrenergic alpha,Receptor Agonists, alpha-Adrenergic,alpha-Adrenergic Agonist,alpha-Adrenergic Agonists,alpha-Adrenergic Receptor Agonist,Adrenergic alpha Agonist,Adrenergic alpha Agonists,Adrenergic alpha Receptor Agonist,Adrenergic alpha Receptor Agonists,Agonist, Adrenergic alpha-Receptor,Agonist, alpha-Adrenergic,Agonist, alpha-Adrenergic Receptor,Agonists, Adrenergic alpha-Receptor,Agonists, alpha-Adrenergic,Agonists, alpha-Adrenergic Receptor,Receptor Agonist, alpha-Adrenergic,Receptor Agonists, alpha Adrenergic,alpha Adrenergic Agonist,alpha Adrenergic Agonists,alpha Adrenergic Receptor Agonist,alpha Adrenergic Receptor Agonists,alpha-Agonist, Adrenergic,alpha-Agonists, Adrenergic,alpha-Receptor Agonist, Adrenergic,alpha-Receptor Agonists, Adrenergic
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
D000833	Animals, Suckling	Young, unweaned mammals. Refers to nursing animals whether nourished by their biological mother, foster mother, or bottle fed.	Animal, Suckling,Suckling Animal,Suckling Animals
D013495	Supraoptic Nucleus	Hypothalamic nucleus overlying the beginning of the OPTIC TRACT.	Accessory Supraoptic Group,Nucleus Supraopticus,Supraoptic Nucleus of Hypothalamus,Accessory Supraoptic Groups,Group, Accessory Supraoptic,Groups, Accessory Supraoptic,Hypothalamus Supraoptic Nucleus,Nucleus, Supraoptic,Supraoptic Group, Accessory,Supraoptic Groups, Accessory,Supraopticus, Nucleus