Integration between the rostral ventrolateral medulla and the paraventricular hypothalamic nucleus during activation of arterial chemoreceptors: possible involvement of catecholaminergic mechanisms.

Author(s)

Talita de Melo e Silva

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2016-04-15

Examining board members

Thiago dos Santos Moreira; Newton Sabino Canteras; Sergio Luiz Domingues Cravo; Lisete Compagno Michelini; Andre Henrique Freiria Oliveira

• Advisor: Thiago dos Santos Moreira

Abstract

The reduction in the O2 partial pressure is detected by the peripheral chemoreceptors that send information to central nervous system to correct the homeostasis. Neuroanatomical studies show that C1 neurons send projections to the paraventricular hypothalamic nucleus (PVH), but rather describe the involvement of this pathway in a hypoxic situation. Furthermore, the potential involvement of neuroimmune mechanisms in cardiorespiratory neural control during hypoxia is unclear. In this study we show that catecholaminergic neurons localized in rostral ventrolateral medulla (RVLM) / C1 cells activated by hypoxia send projections to the PVH, and the integrity of these neurons is essential for PVH neurons be activated by hypoxia. Moreover, treatment with Minocycline changed the expression of inflammatory mediators in RVLM and PVH, the expression of Fos in these nucleus, and respiratory and autonomic responses elicited by hypoxia. These findings provide an important characterization of the distribution of catecholaminergic RVLM / C1 neurons that are activated by hypoxia and project to the PVH. In addition to showing that hypoxia can trigger neuroimmune mechanisms that possibly involve the microglia activity and also recruit the C1/PVH neural pathway. (AU)

• FAPESP's process: 13/00401-5 - Integration between rostroventrolateral medulla and paraventricular nucleus during arterial chemoreceptor activation: possible involvement of catecholaminergic mechanisms
• Grantee: Talita de Melo e Silva
• Support Opportunities: Scholarships in Brazil - Doctorate