Differential projections from the lateral habenula to the rostromedial tegmental nucleus and ventral tegmental area in the rat

Autor(es)

Goncalves, Luciano ^{[1, 2]} ; Sego, Chemutai ^{[1, 3]} ; Metzger, Martin ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, BR-05508900 Sao Paulo - Brazil

^[2] Univ Fed Triangulo Mineiro, Dept Human Anat, BR-38025180 Uberaba - Brazil

^[3] Univ Sao Paulo, Inst Biomed Sci, Dept Anat, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF COMPARATIVE NEUROLOGY; v. 520, n. 6, p. 1278-1300, APR 15 2012.
• Citações Web of Science: 59

Resumo

The mesopontine rostromedial tegmental nucleus (RMTg) is a mostly ?-aminobutyric acid (GABA)ergic structure believed to be a node for signaling aversive events to dopamine (DA) neurons in the ventral tegmental area (VTA). The RMTg receives glutamatergic inputs from the lateral habenula (LHb) and sends substantial GABAergic projections to the VTA, which also receives direct projections from the LHb. To further specify the topography of LHb projections to the RMTg and VTA, small focal injections of the anterograde tracer Phaseolus vulgaris leucoagglutinin were aimed at different subdivisions of the LHb. The subnuclear origin of LHb inputs to the VTA and RMTg was then confirmed by injections of the retrograde tracer cholera toxin subunit b into the VTA or RMTg. Furthermore, we compared the topographic position of retrogradely labeled neurons in the RMTg resulting from VTA injections with that of anterogradely labeled axons emerging from the LHb. As revealed by anterograde and retrograde tracing, LHb projections were organized in a strikingly topographic manner, with inputs to the RMTg mostly arising from the lateral division of the LHb (LHbL), whereas inputs to the VTA mainly emerged from the medial division of the LHb (LHbM). In the RMTg, profusely branched LHb axons were found in close register with VTA projecting neurons and were frequently apposed to the latter. Overall, our findings demonstrate that LHb inputs to the RMTg and VTA arise from different divisions of the LHb and provide direct evidence for a disynaptic pathway that links the LHbL to the VTA via the RMTg. J. Comp. Neurol. 520:12781300, 2012. (C) 2011 Wiley Periodicals, Inc. (AU)

• Processo FAPESP: 07/59799-7 - Composicao de receptores e quimioarquitetura de neuronios no complexo nucleo tegmental latero-dorsal/nucleo tegmental pedunculo-pontino que projetam para a area tegmental ventral no rato.
• Beneficiário: Chemutai Sego
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 04/06790-4 - Composição de receptores de dopamina e glutamato nos neurônios imunopositivos para a fosfoproteina neuronal DARPP-32 no córtex pré-frontal de ratos
• Beneficiário: Martin Andreas Metzger
• Modalidade de apoio: Auxílio à Pesquisa - Regular