High blood pressure (HBP) is characterized by chronic elevation of blood pressure levels. There are several evidences that elevated blood pressure is initiated and maintained by neurogenic factors, which may be related to changes in the brain nuclei responsible for autonomic regulation of the cardiovascular system, such as nucleus of the solitary tract (NTS), the rostral ventrolateral medulla (RVLM), and the paraventricular nucleus (PVN). Exercise training is strictly related to an improvement of hypertension because it can lead to a decrease in heart rate with a consequent decrease in blood pressure, which is related to neurochemical changes among NTS-PVN-NTS pathways, with consequent decrease in sympathetic outflow to the heart and vessels. Our hypothesis is that autonomic imbalance is related to changes in the expression of genes of brain nuclei involved in cardiovascular control that can be modulated by both age and physical activity. Thus, the aim of this study is to identify the putative transcription factors of the hypothalamus and brainstem autonomic nuclei that could be related to the protective effect of exercise training in aging SHR. In order to reach our goal we will be using SHR and WKY (normotensive) 12-14 months of age, trained for 8 weeks. Evaluations of the cardiovascular parameters, baroreflex sensitivity, autonomic balance, blood pressure and heart rate variability, gene (RT-PCR) and protein (Western Blott) expression of hypothalamus and brainstem autonomic nuclei will be performed at week 0, 1, 2, 4 and 8 of trained (T) and sedentary (S) SHR and WKY groups.
News published in Agência FAPESP Newsletter about the scholarship: