Plasma levels of both atrial natriuretic factor (ANF) and vasoconstrictor neurohormones are often increased in patients with congestive heart failure (CHF). It has been speculated that ANF is a counterregulatory hormone that influences regional blood flow and sodium balance in human patients by either direct vasorelaxation or by inhibiting the release of other vasoconstrictor neurohormones. The exact relation of increased ANF levels to regional vascular resistance and vasoconstrictor neurohormones has not previously been documented. Thus, we examined the relation between plasma ANF levels, levels of vasoconstrictor neurohormones, and forearm, splanchnic and renal blood flow in 20 normal subjects and in 17 patients with chronic CHF. The plasma ANF level was directly correlated with the plasma norepinephrine concentration (r = 0.83, p less than 0.01), plasma epinephrine concentration (r = 0.46, p less than 0.01), plasma renin activity (r = 0.50, p less than 0.01), plasma angiotensin II concentration (r = 0.79, p less than 0.01) and plasma vasopressin concentrations (r = 0.65, p less than 0.01). Positive correlations existed between plasma ANF levels and the calculated vascular resistances, i.e., between ANF and forearm vascular resistance (r = 0.41, p less than 0.05), splanchnic vascular resistance (r = 0.74, p less than 0.01) and renal vascular resistance (r = 0.66, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)