title: Stimulation of catecholaminergic neurons in the ventral medulla by various stressors monitored with in vivo electrochemistry.
abstract: Catecholaminergic metabolism in the A1 cell group of the ventrolateral medulla oblongata was followed after application of 3 interoceptive stressful stimuli by monitoring the extracellular concentration of 3,4-dihydroxyphenylacetic acid (DOPAC) with an in vivo voltammetric approach. These stimuli provoked an increase of the DOPAC signal with different time course and amplitude. Histamine led to a maximal 200% increase that vanished within two hours. Insulin induced a long-lasting increase of up to 350% that could be reversed by glucose infusion. Electrical stimulation of the sciatic nerve triggered an immediate increase of up to 140% which stopped with the ending of the stimulation. The time-course of this activation is compatible with a possible involvement of catecholaminergic afferents from the A1 group projecting to the paraventricular nucleus in the stimulation of the hypothalamic neurosecretory cells elicited by the stressors.
authors.affiliation: INSERM U 171/CNRS URA 1195, Centre Hospitalier Lyon Sud, Pierre Benite, France.
authors.forename: A
authors.initials: A
authors.lastname: Rehorek
authors.forename: J
authors.initials: J
authors.lastname: Lachuer
authors.forename: P
authors.initials: P
authors.lastname: Brun
authors.forename: F
authors.initials: F
authors.lastname: Gonon
authors.forename: M
authors.initials: M
authors.lastname: Tappaz
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis / Q000378:metabolism*; D000818:Animals; D004558:Electric Stimulation; D004563:Electrochemistry / Q000379:methods; D006632:Histamine / Q000494:pharmacology; D007003:Hypoglycemia / Q000503:physiopathology; D007328:Insulin / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D008526:Medulla Oblongata / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D012584:Sciatic Nerve / Q000502:physiology*; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D007328:Insulin; D015102:3,4-Dihydroxyphenylacetic Acid; D012965:Sodium Chloride; D006632:Histamine