title: Developmentally different onset of alpha 1- and alpha 2-adrenergic responses in the neonatal rat dorsal motor nucleus of the vagus in vitro.
abstract: Development of noradrenergic responses in the rat dorsal motor nucleus of the vagus (DMV) from postnatal days 0 to 22 was studied by a conventional microelectrode technique using brain slice preparations. Between postnatal days 0 and 6, noradrenaline (NA) caused only alpha 1-adrenoceptor-mediated depolarizations. By postnatal day 14, alpha 2-adrenoceptor-mediated hyperpolarization appeared. During the next postnatal week, the response pattern to NA became similar to that in adults, including both alpha 1- and alpha 2-adrenergic responses. These results suggest that alpha 2-adrenergic responses in DMV neurons are absent at birth but develop rapidly in the 3 weeks after birth. Furthermore, alpha 1-adrenoceptors have already been functioning in the fetal period.
authors.affiliation: Department of Physiology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Fukuda
authors.forename: J
authors.initials: J
authors.lastname: Nabekura
authors.forename: C
authors.initials: C
authors.lastname: Ito
authors.forename: C R
authors.initials: CR
authors.lastname: Plata-Salamán
authors.forename: Y
authors.initials: Y
authors.lastname: Oomura
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000320:Adrenergic Fibers / Q000378:metabolism / Q000502:physiology*; D000375:Aging / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D066298:In Vitro Techniques; D009638:Norepinephrine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D014630:Vagus Nerve / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology
chemical_list: D011942:Receptors, Adrenergic, alpha; D009638:Norepinephrine