Vasodilation promoted by (E,E)-farnesol involving ion channels in human umbilical arteries

BACKGROUND: (E,E)-farnesol is a sesquiterpene alcohol derived from plants and animals that exhibits pharmacological properties in the cardiovascular system. However, its effects on human umbilical vessels remain unknown. PURPOSE: Thus, this study aims to characterize the vasodilatory effect of (E,E)-farnesol in human umbilical arteries (HUA). STUDY DESIGN: The tissue is obtained from pregnant women over 18 years of age, normotensive, and without prepartum complications. After collected, the tissue was segmented and dissected to remove Wharton's jelly and obtain the umbilical arteries segments. METHODS: HUA segments were isolated and sectioned into rings that were subjected to isometric tension recordings in an organ bath. RESULTS: (E,E)-farnesol (1 μmol/L to 1 mmol/L) promoted vasodilatory effect in HUA preparations, affecting basal tone, and inhibiting the electromechanical coupling induced by KCl 60 mmol/L with greater potency (EC(50) 225.3 μmol/L) than the pharmacomechanical coupling induced by 5-HT 10 μmol/L (EC(50) 363.5 μmol/L). In the absence of extracellular calcium, pharmacomechanical coupling was also abolished, and contractions induced by CaCl(2) or BaCl(2) were attenuated by (E,E)-farnesol indicating a possible direct inhibition of L-type VOCC as a mechanism of the vasodilatory effect. The vasodilator efficacy of (E,E)-farnesol on reduction of vasocontraction induced by the presence of tetraethylammonium (1 or 10 mmol/L), 4-aminopyridine (1 mmol/L) and glibenclamide (10 μmol/L) suggesting a possible influence of different potassium channels (BK(Ca), K(V) and K(ATP)). CONCLUSION: These results suggest that (E,E)-farnesol may be a promising pharmacological candidate for obstetric hypertensive disorders.