Adaptive changes of beta-adrenergic receptors after neonatal locus coeruleus lesion: regulation of serotoninergic unit activity.
Spontaneous activity of 5-hydroxytryptamine (5-HT) neurons in the dorsal raphe nucleus (DRN) was recorded in adult rats that had undergone a bilateral locus coeruleus (LC) lesion during the neonatal period. The susceptibility of this neuronal firing to beta-adrenergic manipulation was tested. Microiontophoretic application of the beta-blockers d,l-propranolol and acebutolol inhibited the firing of DRN cells in lesioned rats but not in control animals. This effect was specific to beta-receptors since the effects of pharmacological manipulation of other receptors--5-HT, gamma-aminobutyric acid (GABA), alpha-adrenoceptors--were identical in lesioned and control animals. The present data demonstrate that a neonatal noradrenergic lesion allowed the persistence of a beta-regulation of DRN neuronal firing, which in young rats is normally only transient.
Lanfumey
L
L
INSERM U288, CHU Pitié-Salpêtrière, Paris, France.
Adrien
J
J
D000070:Acebutolol / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D008125:Locus Coeruleus / Q000378:metabolism* / Q000502:physiology; D009473:Neuronal Plasticity; D011433:Propranolol / Q000494:pharmacology; D011903:Raphe Nuclei / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D012701:Serotonin / Q000502:physiology*
D011943:Receptors, Adrenergic, beta; D012701:Serotonin; D000070:Acebutolol; D011433:Propranolol