Hypertension and a digoxin-like substance in the plasma of dialysis patients: possible marker for a natriuretic hormone.

Maintenance hemodialysis patients were randomly assigned to two groups based on the presence or absence of predialysis hypertension. Clinical profiles of the patients in the two groups were comparable except that there were more Blacks in the hypertensive group and that all the patients in this group received antihypertensive medications. Despite not taking any digitalis preparations, 10 of 12 hypertensives had measurable digoxin-like immunoreactive substance (DLIS) in their plasma. None of the 11 normotensives had detectable DLIS. Significantly higher (p less than 0.03) systemic vascular resistance was noted in hypertensives with DLIS compared to normotensives and hypertensives without DLIS. We propose that DLIS itself may be or may represent a marker for some vasopressive substance, possibly natriuretic hormone.