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Plasma histamine concentration during propranolol induced bronchoconstriction
Thorax
|December 1, 1985
Summary
Propranolol can cause bronchoconstriction in asthma patients by affecting beta adrenoceptors. This study found no evidence that this reaction is caused by increased histamine release from mast cells.
Area of Science:
- Pharmacology
- Respiratory Medicine
- Immunology
Background:
- The mechanism of propranolol-induced bronchoconstriction in asthma is unclear.
- Airway beta-adrenoceptors are not innervated by sympathetic nerves, and circulating adrenaline levels are not elevated.
Purpose of the Study:
- To investigate the mechanism of propranolol-induced bronchoconstriction in mild asthma.
- To determine if mast cell mediator release contributes to this effect.
Main Methods:
- 14 subjects with mild asthma received a propranolol infusion (10 mg over 27 minutes).
- Peak expiratory flow (PEF) was measured to assess bronchoconstriction.
- Plasma histamine concentrations were measured to evaluate mast cell degranulation.
Main Results:
- Nine subjects (
- responders
- ) showed a significant decrease in PEF (17-51% of baseline).
- Five subjects (
- non-responders
- ) had minimal PEF changes (≤12% of baseline).
- No consistent changes in plasma histamine were observed in either group.
Conclusions:
- Propranolol can induce bronchoconstriction in some individuals with mild asthma.
- The mechanism does not appear to involve increased mast cell mediator release.