Expression/activity of ascending noradrenergic pathways to the hypothalamus: Effects of sinoaortic denervation and aerobic training.

• Grant number: 11/15676-4
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2012
• End date: July 31, 2013
• Field of knowledge: Biological Sciences - Physiology - General Physiology
• Principal Investigator: Lisete Compagno Michelini
• Grantee: Carla Rocha dos Santos
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The arterial baroreceptors are the most important peripheral receptors in short-term control of arterial pressure (AP), providing adjustments of sympathetic and parasympathetic control. These adjustments involved not only the brain stem pathways but also suprabulbar pathways, responsible for the modulation of circulatory responses in specific situations, such as exercise. Afferent information conveyed to the NTS is transmitted by noradrenergic (NORergic) ascending projections to the pre-autonomic neurons of the paraventricular nucleus of the hypothalamus (PVN) that are vasopressinergic (VPergic) and oxytocinergic (OTergic). These neurons project back to the brain stem areas involved in cardiovascular control, closing a modulatory circuit. Studies from our laboratory have shown that exercise training (T) increases the excitability of VPergic and OTergic descending projections from the PVN to the NTS, facilitating the autonomic control of the heart and vessels. Information on the effects of T on the activity of ascending NORergic projections are scarce. A previous study from our laboratory showed increased density of synaptic buttons immunoreactive for dopamine ²-hydroxylase in OTergic pre-autonomic neurons. Nothing is known about the effects of T on ascending projections to VPergic neurons in the PVN, also involved in the modulation of autonomic control. It is also unknown what stimulus triggers these changes. Since sinoaortic denervation (SAD) blocks the beneficial effects of T on cardiovascular parameters, we hypothesized that the information carried by the afferent signaling (baroreceptors) drives the plastic changes in the central autonomic pathways induced by T. Therefore we sought now to evaluate SAD effects, associated or not with T, on the plasticity of NORergic ascending pathways to the PVN, as well as to compare T-induced plastic changes on VPergic and OTergic pre-autonomic neurons.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SANTOS, C. R.; RUGGERI, A.; CERONI, A.; MICHELINI, L. C.. Exercise training abrogates age-dependent loss of hypothalamic oxytocinergic circuitry and maintains high parasympathetic activity. Journal of Neuroendocrinology, v. 30, n. 8, SI, AUG 2018. (15/24935-4, 11/51410-9, 11/15676-4)

SANTOS, C. R.; RUGGERI, A.; CERONI, A.; MICHELINI, L. C.. Exercise training abrogates age-dependent loss of hypothalamic oxytocinergic circuitry and maintains high parasympathetic activity. Journal of Neuroendocrinology, v. 30, n. 8, p. 13-pg., 2018-08-01. (15/24935-4, 11/51410-9, 11/15676-4)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

SANTOS, Carla Rocha dos. Expression/activity of ascending noradrenergic pathways to the hypothalamus: effects of sinoaortic denervation and aerobic training.. 2013. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) São Paulo.