Atrial Natriuretic Factor: A New Hormone of Cardiac Origin

Abstract

This chapter presents atrial natriuretic factor (ANF). Although there are several major issues that await resolution, a general concept of the possible role of this new hormone is beginning to take shape. The information available at present does not permit any definitive conclusions about the role of ANF in the physiological or pathological processes. The actions of infused ANF, together with its distribution in the central nervous system, suggest a fundamental interaction with the hormonal and neural control of fluid and electrolyte balance and of arterial pressure and the circulation. In addition to its direct and indirect effects on renal excretory function, there is circumstantial evidence that ANF might regulate vascular volume by increasing capillary permeability. There is also evidence that increased levels of plasma ANF can be sustained chronically in pathologic states, such as congestive heart failure, characterized by marked volume overload and chronic increases in atrial wall tension, however, there is a little indication at present that ANF is involved in the long-term regulation of extracellular volume, renal function or arterial pressure under normal conditions. Although there has been considerable excitement over its potential as a therapeutic agent, it will be necessary first to have a clearer understanding of the role of endogenous ANF in health and disease.