Effects of transcranial direct current stimulation on the central cardiovascular regulation of spontaneously hypertensive rats

• Grant number: 22/00280-2
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: July 01, 2022
• End date: June 30, 2023
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Bruno Rodrigues
• Grantee: Olivia Moraes Ruberti
• Supervisor: Andrew M. Allen
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: University of Melbourne, Australia
• Associated to the scholarship: 19/02975-5 - Effects of transcranial direct-current stimulation (tDCS) on blood pressure of spontaneously hypertensive rats (SHR): a functional, inflammatory and epigenetic approach, BP.DR

Abstract

Problem Statement: Arterial hypertension (AH) is a multifactorial disease, with cardiovascular autonomic imbalance considered a leading cause of its complications. The use of brain stimulation techniques, such as noninvasive transcranial direct current stimulation (tDCS) of the cerebral cortex, may be a promising approach to reduce blood pressure (BP) in AH. However, the mechanisms by which tDCS can influence BP levels and its control by the autonomic nervous system (ANS) have not yet been elucidated. Aim: We aim to evaluate the effects of 8 sessions of bimodal tDCS on BP in spontaneously hypertensive rats (SHR) and Wistar rats and to examine the brain pathways involved using optogenetic approaches. Methods: The animals will be randomly divided into six experimental groups: control SHR rats (SHR-CTR), SHR submitted to tDCS (SRH-tDCS), SHR submitted to sham stimulation (SHR-SHAM), control Wistar rats (WH-CTR), Wistar rats submitted to tDCS (WH-tDCS) and Wistar rats submitted to sham stimulation (WH-SHAM). All animals will undergo surgery to implant telemetry probes. After recovery, tDCS or sham stimulation protocol will be performed. The BP will be measured every day during, and after, stimulation. After the 8 days of intervention, the animals will be euthanized and the brains removed for immunohistochemistry analysis of activated brain regions. The immunohistochemical analysis will be used to determine areas stimulated by tDCS, and in subsequent protocols, activity in these regions will be modulated using viral optogenetic approaches during tDCS protocols. Perspective: This study will shed light on the physiological basis for treating AH with tDCS. (AU)