Investigation of the Activation Pattern of Neurons of the Paraventricular Nucleus of the Hypothalamus Projecting to the Medulla Oblongata and Spinal Cord in Response to Osmotic Challenge with Salt Overload

• Grant number: 24/17113-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2025
• End date: December 31, 2025
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Vagner Roberto Antunes
• Grantee: Pedro Sousa Soares
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Blood pressure (BP) is regulated by various mechanisms, among which neural control mediated by the central nervous system (CNS) stands out. The paraventricular nucleus of the hypothalamus (PVN) plays a crucial role in modulating sympathetic activity, which directly influences BP. Dysfunctions in cardiovascular sympathetic centers can lead to the development of neurogenic hypertension. Systemic arterial hypertension (SAH) is a multifactorial condition and one of the main risk factors for cardiovascular diseases, accounting for 50% of cardiovascular deaths in Brazil. There is a strong correlation between high sodium intake and the development of SAH, with evidence showing that sodium overload results in chronic activation of the circumventricular organs (CVOs) of the hypothalamus and subsequent activation of the PVN. This study aims to investigate the hypothesis that oxytocinergic and vasopressinergic neurons of the PVN, which project to the rostral ventrolateral medulla (RVLM) and the intermediolateral column (IML), are differentially activated in response to sodium overload. Using Wistar rats as a model, neuro-surgical, vascular surgery, and immunofluorescence techniques will be applied to neurochemically and anatomically characterize these neural pathways.