An emerging relationship between peripheral sympathetic nervous activity and atrial natriuretic factor.

The sympathetic nervous system and atrial natriuretic factor (ANF) are intimately involved in sodium, volume and blood pressure homeostasis, particularly in response to volume and pressure overloads. Although rapid progress in this field indicates several levels of interaction between both systems, the role of sympathetic nervous activity (SNA) in ANF release remains a controversial topic. There is growing evidence that ANF is an inhibitory modulator of sympathetic outflow (which in turn, may contribute to ANF's effect) and, vice-versa, SNA attenuates the target actions of ANF. Compensatory sympathetic reactions to changes induced by ANF may also have an overriding influence on its target actions. Dopamine appears to play a special role in these interactions. It is not only a precursor of norepinephrine but probably fulfills an independent function in the regulation of salt balance, similar in many respects to that of ANF.