The vasodilator effect of Eugenol on uterine artery - potential therapeutic applications in pregnancy-associated hypertension.

Preeclampsia, a gestational associated hypertension, has been reported in 6-8% of pregnant women worldwide leading to premature delivery and low birth weight of newborn due to reduced blood flow to placenta. Although several vasodilators (Methyl dopa, hydralazine, β-blockers and diuretics) are currently in use to treat preeclampsia, still there is a search for safer drugs with better efficacy. Lately, antihypertensive vasodilators from natural sources are gaining importance in treating preeclampsia. Eugenol (Eug), a natural essential oil, has been traditionally used in health and food products without any risk. In the present study, ex vivo experiments were designed to examine the vasorelaxation effect of Eug and its signaling pathways in a middle uterine artery (MUA) of pregnant Capra hircus (Ch). In presence of different blockers (L-NAME, indomethacin, ODQ, Ouabain, glibenclamide, 4-AP, Ba², Carbenoxolone and 18β Glycyrrhetinic acid), Eug-induced concentration-dependent vasorelaxation response was elicited. The results showed that Eug caused a greater vasorelaxation effect in the MU of pregnant animals, which is mediated by potential activation of eNOS, K_ATP channels, and K_ir channels with moderate activation of Na⁺- K⁺- ATPase and sGC and MEGJ. These findings provide a strong basis for developing Eug as a therapeutic candidate in the treatment of pregnancy-associated hypertension.