Glycycoumarin from Glycyrrhizae Radix acts as a potent antispasmodic through inhibition of phosphodiesterase 3 - Sato, Y; Akao, T; He, J X; Nojima, H; Kuraishi, Y; Morota, T; Asano, T; Tani, T (J Ethnopharmacol, 2006)