Abstract
A selective α2-adrenergic antagonist, midaglizole, has been recently reported to have efficacy in patients with asthma. To understand the mechanisms, we investigated the effect of midaglizole on the cyclic 3′,5′-adenosine monophosphate (cAMP) production in human mononuclear cells (MNCs). MNCs were separated by a histopaque gradient from 10 normal subjects and 10 subjects with asthma. cAMP was measured by RIA kits. Midaglizole (10 μmol/L) significantly enhanced isoproterenol-induced cAMP production in both groups, although midaglizole (from 1 to 100 μmol/L) did not increase the cAMP production by itself. The percent increase in cAMP was more in subjects with asthma (183.8%) than in normal subjects (140.4%); however, the absolute increase was not different. Platelet-activating factor has been demonstrated to inhibit β-agonist-induced cAMP production in several mammalian tissues, including human MNCs. Midaglizole also prevented platelet-activating factor-induced desensitization of the cAMP response to isoproterenol in MNCs. These findings suggest that midaglizole may be a useful additional agent for the therapy of bronchial asthma through an enhancement of the cAMP production.
Original language | English (US) |
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Pages (from-to) | 722-729 |
Number of pages | 8 |
Journal | The Journal of Allergy and Clinical Immunology |
Volume | 89 |
Issue number | 3 |
DOIs | |
State | Published - Mar 1992 |
All Science Journal Classification (ASJC) codes
- Immunology and Allergy
- Immunology