Sensing danger through the olfactory system: the role of the hypothalamic dorsal premammillary nucleus

Autor(es)

Canteras, Newton S. ^[1] ; Kroon, Juliana A. V. ; Do-Monte, Fabrício H. M. ; Pavesi, Eloisa ; Carobrez, Antonio P.

Afiliação do(s) autor(es)

^[1] Universidade de São Paulo (USP). Instituto de Ciências Biomédicas. Departamento de Anatomia - Brasil

• Tipo de documento: Artigo Científico
• Fonte: NEUROSCIENCE AND BIOBEHAVIORAL REVIEWS; v. 32, n. 7, p. 1228-1235, Sept. 2008.
• Área do conhecimento: Ciências Biológicas - Fisiologia
• Assunto(s): Olfato Transmissão nervosa Hipotálamo Receptores de N-metil-D-aspartato Estados emocionais Medo

Resumo

The dorsal premammillary nucleus (PMd) has a critical role on the expression of defensive responses to predator odor. Anatomical evidence suggests that the PMd should also modulate memory processing through a projecting branch to the anterior thalamus. By using a pharmacological blockade of the PMd with the NMDA-receptor antagonist 2-amino-5-phosphonopentanoic acid (AP5), we were able to confirm its role in the expression of unconditioned defensive responses, and further revealed that the nucleus is also involved in influencing associative mechanisms linking predatory threats to the related context. We have also tested whether olfactory fear conditioning, using coffee odor as CS, would be useful to model predator odor. Similar to cat odor, shock-paired coffee odor produced robust defensive behavior during exposure to the odor and to the associated context. Shock-paired coffee odor also up-regulated Fos expression in the PMd, and, as with cat odor, we showed that this nucleus is involved in the conditioned defensive responses to the shock-paired coffee odor and the contextual responses to the associated environment. (AU)

• Processo FAPESP: 05/59286-4 - Bases neurais dos comportamentos motivados
• Beneficiário: Newton Sabino Canteras
• Modalidade de apoio: Auxílio à Pesquisa - Temático