Biomaterial Database

Immunocytochemical and physiological evidence of a synapse between dopamine- and luteinizing hormone releasing hormone-containing neurons in the ewe median eminence. 1989

R O Kuljis, and J P Advis

Department of Neurology, Yale University School of Medicine, New Haven, CT 06510.

Immunocytochemical labeling revealed that the arcuate nucleus (ARN) of the ewe's hypothalamus contains numerous tyrosine hydroxylase (TH)-positive neurons, that appear to lack dopamine-beta-hydroxylase (DBH)-like immunoreactivity. Axons of these presumed dopaminergic neurons converge in the median eminence (ME) with Luteinizing Hormone Releasing Hormone (LHRH)-containing axons originating mostly from neurons situated in the medial preoptic area. Electron microscopic double labeling revealed synaptic contacts between TH-positive presynaptic profiles and LHRH-containing postsynaptic elements. Samples of ME, ARN, paraarcuate and lateral hypothalamus were dissected and incubated to assess LHRH release and tissue content. Only ME-LHRH release was significantly reduced in the presence of dopamine (DA). All other regions released equal amounts with and without DA. Thus, a presynaptic dopaminergic inhibition of LHRH-containing axons at the level of the ME might contribute to the regulation of LHRH release into the portal vessels.

UI	MeSH Term	Description	Entries
D007124	Immunoenzyme Techniques	Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.	Antibody Enzyme Technique, Unlabeled,Enzyme Immunoassay,Enzyme-Labeled Antibody Technique,Immunoassay, Enzyme,Immunoperoxidase Techniques,Peroxidase-Antiperoxidase Complex Technique,Peroxidase-Labeled Antibody Technique,Antibody Enzyme Technic, Unlabeled,Enzyme-Labeled Antibody Technic,Immunoenzyme Technics,Immunoperoxidase Technics,Peroxidase-Antiperoxidase Complex Technic,Peroxidase-Labeled Antibody Technic,Antibody Technic, Enzyme-Labeled,Antibody Technic, Peroxidase-Labeled,Antibody Technics, Enzyme-Labeled,Antibody Technics, Peroxidase-Labeled,Antibody Technique, Enzyme-Labeled,Antibody Technique, Peroxidase-Labeled,Antibody Techniques, Enzyme-Labeled,Antibody Techniques, Peroxidase-Labeled,Enzyme Immunoassays,Enzyme Labeled Antibody Technic,Enzyme Labeled Antibody Technique,Enzyme-Labeled Antibody Technics,Enzyme-Labeled Antibody Techniques,Immunoassays, Enzyme,Immunoenzyme Technic,Immunoenzyme Technique,Immunoperoxidase Technic,Immunoperoxidase Technique,Peroxidase Antiperoxidase Complex Technic,Peroxidase Antiperoxidase Complex Technique,Peroxidase Labeled Antibody Technic,Peroxidase Labeled Antibody Technique,Peroxidase-Antiperoxidase Complex Technics,Peroxidase-Antiperoxidase Complex Techniques,Peroxidase-Labeled Antibody Technics,Peroxidase-Labeled Antibody Techniques,Technic, Enzyme-Labeled Antibody,Technic, Immunoenzyme,Technic, Immunoperoxidase,Technic, Peroxidase-Antiperoxidase Complex,Technic, Peroxidase-Labeled Antibody,Technics, Enzyme-Labeled Antibody,Technics, Immunoenzyme,Technics, Immunoperoxidase,Technics, Peroxidase-Antiperoxidase Complex,Technics, Peroxidase-Labeled Antibody,Technique, Enzyme-Labeled Antibody,Technique, Immunoenzyme,Technique, Immunoperoxidase,Technique, Peroxidase-Antiperoxidase Complex,Technique, Peroxidase-Labeled Antibody,Techniques, Enzyme-Labeled Antibody,Techniques, Immunoenzyme,Techniques, Immunoperoxidase,Techniques, Peroxidase-Antiperoxidase Complex,Techniques, Peroxidase-Labeled Antibody
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
D008473	Median Eminence	Raised area at the infundibular region of the HYPOTHALAMUS at the floor of the BRAIN, ventral to the THIRD VENTRICLE and adjacent to the ARCUATE NUCLEUS OF HYPOTHALAMUS. It contains the terminals of hypothalamic neurons and the capillary network of hypophyseal portal system, thus serving as a neuroendocrine link between the brain and the PITUITARY GLAND.	Eminentia Mediana,Medial Eminence,Eminence, Medial,Eminence, Median,Eminences, Medial,Eminentia Medianas,Medial Eminences,Mediana, Eminentia,Medianas, Eminentia
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
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
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
D001369	Axons	Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.	Axon
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