Proxyphylline

Proxyphylline is a dual of adenosine A1/A2a receptor inhibitor and phosphodiesterase (PDE) inhibitor. Proxyphylline acts as a cardiac stimulant vasodilator and bronchodilator.(In Vitro):Proxyphylline has shown vasodilatory and cardiac stimulatory effects. Proxyphylline produces an increase in the coronary flow associated with a definite positive inotropic effect. Proxyphylline inhibits tracheal PDE-activity and half-maximum relaxation of tracheal smooth muscle is obtained with 100 μg/mL proxyphylline(In Vivo):Proxyphylline exhibits bronchodilatory effect. Proxyphylline inhibits cAMP and cGMP hydrolysis in human lung tissue. The apparent inhibition constant of proxyphylline is 0.06-0.7 mM at low cAMP concentrations and it is 1.0 mM at high cAMP concentrations.