Module 7: Figure blood pressure control
Hormonal regulation of blood Na+ levels.
Regulation of blood Na+ levels within the vascular system depend upon the control of Na+ filtration and reabsorption by the kidney by a number of systems. A major player is the renin–angiotensin system (RAS) which is activated by the release of renin from renin-producing cells within the juxtaglomerular apparatus (JGA). The resulting formation of angiotensin II then acts on a number of systems as described in the text.