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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Theophylline has an antagonistic interaction with which of the following receptor?
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The correct answer is  Theophylline has an antagonistic interaction with adenosine receptors. Adenosine acts as a local mediator in CNS, CVS and other organs, cause contraction of smooth muscles especially bronchial, dilates cerebral blood vessels, depress cardiac pacemaker and inhibits gastric secretion. Methylxanthines acts by antagonizing adenosine receptors resulting in opposite effects. Ref: Essentials of Medical Pharmacology, 5th Edition, Page 203