Vascular changes of the blood-brain barrier in hypertensive animals: Effects of the aerobic exercise

Abstract

Despite the intensive research and therapeutic advances made within the last decades, the arterial hypertension is still the main problem of the world health. The hypertension causes changes in the central nervous system (CNS) like, for example, the increase in the blood-brain barrier (BBB) permeability and its consequent disruption, which are important factors of risk for stroke. So, the integrity of the BBB is essential for the CNS homeostasis. The mechanisms of which the hypertension affects the BBB function are still to be determined and a lot of questions remain to be answered. It's known that the angiotensin II (ANG II) has an important role on the BBB disruption, directly modulating the function of the endothelial cells and changing its permeability, through the AT1 receptors, rise on the oxidative stress and inflammation. Experiments in our laboratory have been demonstrating that the low intensity aerobic training is an efficient therapeutic method to reduce the expression and activity of the brain renin-angiotensin system (RAS). Thus, we pretend to investigate the effects of the aerobic training on the permeability of the BBB (extravasation of the fluorescent dye to the encephalic extravascular space, through the immunohistochemistry technique), over the health BBB constituent proteins expression (endothelial barrier antigen and transferrin receptor) and damaged (dysferin, lesion marker), as well to evaluate the expression of AT1 and inflammatory markers (tumoral necrose factor alfa - TNF± - and interleucin 6 - IL-6), with the western-blotting method.