ABSTRACT
Atrial natriuretic peptide (ANP) is one of the circulating hormones with blood pressure related biological actions. This chapter reviews the available data on ANP and sodium transport systems. It presents brief overview on ANP and a more specific discussion of some aspects of the involvement of ANP in hypertensive disorders. Essential hypertension remains a disorder of unknown etiology but for which evidence exists of several abnormalities of blood pressure-related systems and hormones. When ANP actions were uncovered, it soon became clear that essential hypertension could theoretically be a state of lack of ANP or resistance to ANP actions. Plasma ANP levels are often similar in mild to moderate untreated essential hypertension and in aged-matched normotensive controls, although they are reported to be elevated in patients with more severe hypertension. The fact that hypertensives are somewhat hyperresponsive to ANP infusion would also be in keeping with the hypothesis that ANP production is deficient in hypertensives, assuming an up-regulation phenomenon.
