A dopaminergic projection from the dorsal raphe nucleus to the inner ear.
- Author:
Xin-Ming YANG
1
;
Shu-Hui WANG
;
Yi-Da YANG
;
Qing-Lai TANG
;
Ting ZHANG
;
Peng TAN
;
Ke-Ying SONG
;
Qiang-He LIU
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Cats; Ear, Inner; innervation; metabolism; Efferent Pathways; Neurons; metabolism; physiology; Raphe Nuclei; metabolism; physiology
- From: Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2006;41(11):857-860
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the efferent pathway from the dorsal raphe nucleus to the inner ear.
METHODSEleven adult cats weighing 2.0 - 3.0 kg were used. The animals had no middle-ear disease and their auricle reflex was sensitive to sound. They were divided into experimental group (8 cats) and control group (3 cases). The fluorescent tracer cholera toxin subunit-B (CTB) was injected into cat cochlea and the CTB-labelled neurons of dorsal raphe nucleus (DRN) were identified using an immunofluorescence technique after a survival period of 7 days. For studying other fluorescence labelling, the sections containing CTB-labelled neurons were divided into four groups and incubated in antisera directed against tyrosine hydroxylase (TH), serotonin (5-HT), gamma-aminobutyric acid (GABA) and dopamine B-hydroxylase (DBH), respectively. Single-and double-labelled neurons were identified from the DRN.
RESULTS(1) A subpopulation of dorsal raphe nucleus (DRN) neurons were intensely labelled with CTB and these CTB-labelled neurons were densely distributed in a dorsomedial part of the DRN; (2) Four immunolabelling, TH, 5-HT, GABA and DBH were presented throughout the DRN. Of the total population of CTB-labelled neurons, 100% were TH-labelled neurons (double labelling) and no double-stained neuron with 5-HT, GABA and DBH was observed in the DRN.
CONCLUSIONSThere was a projection from DRN to the inner ear and this pathway might be a dopaminergic projection.