Which of the following enzyme is inhibited by Aminophylline ?

Theophylline is a non selective phosphodiesterase inhibitor. Inhibition of this enzyme cause elevation of cellular cAMP and cGMP and cause bronchodilation. Other mechanism of action of Aminophylline includes: Antagonises adenosine receptor Increase release of IL 10 which has anti inflammatory effect It prevents the translocation of the pro-inflammatory transcription factor NF-kB into the nucleus, potentially reducing the expression of inflammatory genes in asthma and COPD. Side effects: Headache Nausea Vomiting Abdominal discomfo Restlessness Increased acid secretion Diuresis At high concentration it cause cardiac arrhythmias Very high concentration causes seizures Ref: Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e chapter 36.