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Updated: May 12, 2026

Bronchial Thermoplasty: A Novel Therapeutic Approach to Severe Asthma
Published on: November 4, 2010
The testosterone paradox in asthma
1Department of Medicine, Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ) - Université Laval, Quebec, QC, Canada.
Abstract:
Asthma and an excessive response to inhaled methacholine, commonly called hyperresponsiveness, are intimately linked. Therefore, factors increasing the methacholine response are expected to contribute to asthma as well. However, this is clearly not the case for testosterone, the predominant sex hormone in males. While testosterone increases the methacholine response, it is rather protective in asthma and experimental asthma. These incompatible observations are referred herein as the 'testosterone paradox', and the chase is now on to unravel its underlying mechanisms.
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