<prompt> Aminophylline inhibits which enzyme -MAOAlcohol dehydrogenasePhosphodieseteraseCytochrome P450  <response>: Ans. is c i.e., Phosphodiesterase o Aminophylline is a preparation of theophylline, where theophylline is complexed with EDTA.o Theophylline is one of the three naturally occurring methylated xanthine alkaloids methyl xanthines - Caffeine, theophylline and theobromine,o Mechanism of actiona Inhibition of phosphodiesterase - degradation of cAMP or cGMPbronchodilatation - increased intracellular cAMP or cGMP.Blockade of adenosine receptorsRelease of Ca2 from sarcoplasmic reticulum especially in skeletal and cardiac muscles.Recently it has been found that theophylline at low doses exert antiinflammatory action by activating a nuclear enzyme, histone deacetylase-2. 