Researchers at University of Tokyo Graduate School of Medicine have uncovered a new mechanism behind salt-sensitive hypertension. They found that a high-salt diet fed to salt-sensitive rats activates a gene called Rac1 in the kidneys; this leads to increased activity of the MR (Mineralocorticoid Receptor) protein and causes elevated blood pressure and kidney damage. Their study showed that Rac1 is regulated by both salt and aldosterone, a hormone that helps control blood pressure. They found that inhibiting Rac1 prevents high blood pressure as well as injury to the glomeruli of the kidney. Rac1 appears to be a major factor in determining salt sensitivity and could prove to be a beneficial target for preventing salt-sensitive hypertension and resultant kidney injury in humans.
New Mechanistic Insight Into Salt-Induced High Blood Pressure, University of Tokyo Graduate School of Medicine, July 18, 2011