A Phenoxazine Compound, 2-Amino-4,4α-dihydro-4α-7-dimethyl-3H-phenoxazine-3-one Reverses the Phenylephrine or High-K⁺ Induced Contraction of Smooth Muscles in Rat Aorta and Guinea Pig Tenia Cecum

Abstract

2-Amino-4,4α-dihydro-4α-7-dimethyl-3H-phenoxazine-3-one (Phx-1) reversed concentration dependently the contraction of both rat aorta and guinea pig tenia cecum induced by phenylephrine or high-K⁺. Since Phx-1 suppresses the responses of human mononuclear cells to phytohemagglutinin, (Akazawa et al. Tohoku J. Exp. Med., 196, 185—192, 2002), Phx-1 may be useful for developing new vasorelaxing agents with immunosuppressive action.