Potentiation of isoprenaline-induced plasma cyclic AMP response by aminophylline in normal and asthmatic subjects.
1 The effect of intravenous aminophylline infusion (6 mg-1 kg in 20 min, then 0.9 mg-1 kg-1 h thereafter) and its interaction with inhaled isoprenaline (800 microgram ex inhaler) on plasma cyclic AMP levels was studied in five normal and five asthmatic subjects. 2 Aminophylline infusion alone did not significantly change plasma cyclic AMP levels in either group. 3 In both groups, the plasma cyclic AMP response to isoprenaline aerosol inhalation was enhanced by aminophylline, although to a lesser degree in the asthmatic subjects. 4 The results provide in vivo evidence consistent with the hypothesis that in man, therapeutic doses of aminophylline may exert their clinical effects by inhibition of cyclic AMP phosphodiesterase.
D000328:Adult; D000628:Aminophylline / Q000494:pharmacology*; D001249:Asthma / Q000097:blood*; D000242:Cyclic AMP / Q000097:blood*; D004357:Drug Synergism; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology*; D008875:Middle Aged; D013997:Time Factors
D000628:Aminophylline; D004492:Edetic Acid; D000242:Cyclic AMP; D007545:Isoproterenol