[Physiological and physiopathological aspects of the atrial natriuretic factor]

The discovery of the atrial natriuretic factor (ANF) has opened a new field in modern biology. After rapid isolation and identification of this new peptide from atrial granules, it is now evident that this new hormone has a wide variety of actions with general implication in the control of vascular tone, sodium and water balance, hormonal secretion as well as neuronal functions. The major mode of action of this hormone is transmitted via its interaction with a membrane enzyme, particulate guanylate cyclase, leading to increases of cGMP levels. This nucleotide is a faithful marker of ANF action correlating with all functions ascribed to ANF up to date. Significant increases of ANF as well as of cGMP have been discovered in heart and renal failure, secondary hypertension and other states with altered salt-water balance, impairment of heart function and particularly increase of atrial pressure. The increases of levels and relative inefficiency of increased ANF have to be carefully interpreted in face of increased levels of cGMP. It can be expected that new pharmacological developments will occur in this area issuing from both our increasing knowledge concerning the peripheral mode of action of this hormone, its physiological implications as well as its pharmacological effectiveness in diseases with altered salt-water balance, cardiac function and blood pressure disregulation.