title: In vivo monitoring of catecholaminergic metabolism in the C1 region of rat medulla oblongata: a comparative study by voltammetry and intracerebral microdialysis.
abstract: In vivo voltammetry or microdialysis was used to monitor catecholaminergic metabolism in the C1 region of the ventrolateral medulla oblongata of anesthetized rats. In vivo voltammetry allowed the recording of a catechol oxidation current (CA.OC) peak in this region. This CA.OC was suppressed after inhibition of monoamine oxidase by pargyline or after inhibition of tyrosine hydroxylase by alpha-methyl-p-tyrosine and was markedly increased after blockade of dopamine-beta-hydroxylase by FLA 63. Similar results were found when intracerebral microdialysis coupled with HPLC and electrochemical detection was used to measure the concentration of 3,4-dihydroxyphenylacetic acid (DOPAC) in the dialysates obtained from the C1 region: The changes in CA.OC and DOPAC concentration in the dialysates exhibited very similar kinetic characteristics in the three pharmacological experiments. These results support the involvement of DOPAC as a major component of the electrochemical signal recorded by voltammetry in the C1 group of adrenergic neurons.
authors.affiliation: Laboratoire de Neuropharmacologie, CNRS UMR 105, Faculté de Pharmacie, Université Claude Bernard, Lyon, France.
authors.forename: L
authors.initials: L
authors.lastname: Lambás-Señas
authors.forename: J Y
authors.initials: JY
authors.lastname: Gillon
authors.forename: J P
authors.initials: JP
authors.lastname: Bouilloux
authors.forename: M
authors.initials: M
authors.lastname: Seccia
authors.forename: M
authors.initials: M
authors.lastname: Buda
authors.forename: B
authors.initials: B
authors.lastname: Renaud
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D002396:Catechols / Q000378:metabolism; D003956:Dialysis / Q000379:methods; D004299:Dopamine beta-Hydroxylase / Q000037:antagonists & inhibitors; D004594:Electrophysiology; D008297:Male; D008526:Medulla Oblongata / Q000378:metabolism*; D008991:Monitoring, Physiologic / Q000379:methods*; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains; D014446:Tyrosine 3-Monooxygenase / Q000037:antagonists & inhibitors
chemical_list: D002395:Catecholamines; D002396:Catechols; D008996:Monoamine Oxidase Inhibitors; D015102:3,4-Dihydroxyphenylacetic Acid; D014446:Tyrosine 3-Monooxygenase; D004299:Dopamine beta-Hydroxylase; C034221:catechol