<prompt> Mechanism of action of theophylline in Bronchial asthma include all of the following Except -Phosphodiesterase inhibitionAdenosine receptor antagonismIncreased histone deacetylationBeta-2 receptor stimulation  <response>: Ans. is d i.e., Beta-2 receptor stimulationo Pneumonia and CHF Cardiopulmonary disease require dose reduction not increased dose.Theophyllineo 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.Proposed mechanisms of action of theophyllineo Phosphodiesterase inhibition Non selectiveo Adenosine receptor antagonism A1 A2o Increased histone Deacetylase activity ed efficacy of corticosteroidso Inhibition of intracellular calcium releaseo Stimulation of catecholamine releaseo Inhibition of NF - a B translocation into the nucleus nuclear translocationo Mediator inhibition Prostaglandins, TNF a 