Shengmai Suppressed Vascular Tension in Umbilical Arteries and Veins of Human and Sheep

Objective—The umbilical cord is a critical pathway between mothers and fetuses, and regulations of umbilical vessel tension are important for fetal growth. Shengmai is an herbal medicine being used in treatments of cardiovascular diseases. However, effects of Shengmai on human blood vessels and related pharmacological mechanisms are unclear. Methods—This study investigated the effects of related mechanisms of Shengmai and its key compounds on human and sheep umbilical arteries and veins using organ bath systems. Key Findings—Shengmai significantly suppressed phenylephrine-stimulated vasoconstriction in umbilical arteries and veins. NG-Nitro-L-arginine Methyl Estercould not change the Shengmai-suppressed vasoconstriction in human and sheep umbilical vessels. Among four key compounds of Shengmai, Ginsenoside Re, Ginsenoside Rb1, Ginsenoside Rg1, and Schisandrin, only Ginsenoside Re showed the significant effect similar to Shengmai’s in the umbilical vessels. In Ca2+-free solution, Ginsenoside Re did not affect vasoconstriction. In addition, caffeine- or phenylephrine-stimulated vasoconstriction were not changed by Ginsenoside Re. Either charybdotoxin or glibenclamide could inhibit Ginsenoside Re-caused inhibition of the stimulated vasoconstriction in both human and sheep umbilical vessels, where 4-aminopyridine did not show the similar inhibitory effect. Conclusion—The results provide new information on Shengmai’s effects and underlying mechanisms in umbilical vessels. Importantly, the information gained offers interesting potential for developing new drugs acting on umbilical cords for fetal medicine.