Increased blood flow to the atria of the heart can stimulate the secretion of the atrial natriuretic factor (ANF). It induces vasodilation (dilation of blood vessels) and thereby, decreases blood pressure. The ANF mechanism acts as a check for the Renin-Angiotensin-Aldosterone (RAAS) pathway. It inhibits the secretion of renin to lower the increased blood pressure. It also promotes the excretion of electrolytes, thereby suppressing sodium reabsorption.