Vasoactive role of endogenous digoxin-like factor in rats with experimental hypertension.

Acute blockade of circulating digoxin-like factor endoxin lowered blood pressure (BP) by a decrease in systemic resistance which was partially compensated by an increased cardiac output. The important participation of circulating endoxin in the maintenance of elevated BP was proved in young animals with DOCA-salt and one-kidney, one-clip (1K1C) Goldblatt hypertension but not in young spontaneously hypertensive rats (SHR). In rats with DOCA-salt as well as with 1K1C hypertension, the role of endoxin differed according to the age at which the hypertensive stimulus was applied. The significant role of the "digoxin-like" factor in BP regulation was found only in young animals. On the other hand, in SHR the participation of endoxin in the maintenance of elevated BP rises with the age. High salt intake prior to sexual maturation seems to be critical for later participation of the "digoxin-like" factor in long-term BP regulation.