Hypertension

High blood pressure or hypertension. The kidneys control blood pressure by regulating the amount of salt in the body and by making the enzyme renin that, along with other substances, controls the constriction of blood vessels. The many causes of high blood pressure include kidney disease; genetic factors such as the so-called "essential hypertension," which is the most common form of high blood pressure in adults; and obesity, which has become a major factor.