theophylline and 1-methyl-3-isobutylxanthine ( mix ) , compounds that block eicosanoid formation and modulate phospholipase a2 activity , inhibited in a dose-dependent manner the formation of both leukotriene b4 ( ltb4 ) and platelet-activating factor ( paf ) by human polymorphonuclear leucocytes ( pmn ) in response to ionophore a23187 .
C0039771
theophylline
C0000096
1-methyl-3-isobutylxanthine