Endogenous ouabain-like factor (OLF) secretion is modulated by nicotinic mechanisms in rat adrenocortical cells.

This study tested the hypothesis that rat adrenocortical secretion of endogenous ouabain-like factor (OLF) is regulated by nicotinic mechanisms. OLF secreted by dispersed cell suspensions of zona glomerulosa (ZG) and fasciculata/reticularis (ZFR) cells was found to co-elute with authentic ouabain by reverse phase HPLC; OLF concentrations in cell supernatants were measured by radioimmunoassay. Nicotine (10(-6) - 10(-3) M) stimulated significant OLF secretion in rat adrenocortical cells.

Elevated blood levels of endogenous ouabain-like factor in preterm versus mature newborns at birth.

Compared to healthy adults, elevated levels of endogenous ouabain-like factor (OLF) have already been shown in the cord blood, and a role of OLF in the maintenance of high Na(+) excretion by reducing tubular sodium reabsorption during intrauterine life was suggested. In this study, we aimed to measure OLF cord blood levels of premature and mature newborns to provide further data on the possible physiological significance of this compound in neonates. OLF was assessed in the cord blood of newborns (28-41 weeks) and in the blood of healthy adults using ouabain radioimmunoassay.