<prompt> Mechanism of action of Theophylline in bronchial asthmaPhosphodiestesrase 4 inhibitionBeta 2 agonismAntichoinergic actionInhibition of mucociliary clearance  <response>: Refer Katzung 11e p 345 Theophylline is used in bronchial asthma. Its mechanise of action is Inhibition of phosphodiestesrase paicularly PDE-4 Antagonism of adenosine receptors Enhancement for histone deacetylation 