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Effect of ketotifen on adenyl cyclase activity in asthmatic patients
J G Castillo1, A Oehling, P M Gamboa
1Department of Allergology, Faculty of Medicine, University of Navarra, Pamplona, Spain.
Abstract:
Employing peripheral blood leucocytes as the model of the study, we proved how ketotifen blocks the inhibiting effect that the antigen induces over the adenyl cyclase activity in asthmatic individuals with sensitization to Dermatophagoides pteronyssinus. The strength of the Ketotifen effect is comparable to that produced on beta-receptor stimulation by isoproterenol. On the other hand, we found that within the same age range, the activity of adenyl cyclase in asthmatic individuals is comparable to healthy individuals, although the response is not the same to isoporoterenol which is greater in the control group. This is probably due to the diminished number of beta-receptors in asthmatic individuals as compared to healthy ones.
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