title: Sex hormones modulate salbutamol-elicited long-term relaxation in isolated bovine tracheal strips.
abstract: Sex hormones are of interest regarding gender differences in the clinical manifestations of airway diseases. No conclusive data are available on the sex hormone modulation of β-adrenoceptor-mediated responses on airways. To this aim, isolated preparations of bovine trachea were used to establish the sex hormone influence on salbutamol-elicited relaxation. This had 2 components, a full acute relaxation followed by a loss of efficacy, close to half of the effect. The remaining half was reverted by the β-blocker, propranolol. The loss of salbutamol-elicited relaxation might reflect the receptor desensitization, as shown by the lack of effect by subsequent administration of salbutamol, and the decrease in the immunostaining of β(2)-adrenoceptors. Sex hormones differently modified the salbutamol-elicited response. Testosterone, but not other androgens or estradiol, had a synergic effect, facilitating the acute relaxation and decreasing the loss of spasmolytic effect, associated with an increase in the latency of desensitization and a decrease in the time taken to reach long-term steady-state tone. These effects, not modified by the antiandrogen flutamide or epithelium removal, seem to be independent of a modulation of β(2)-adrenoceptor desensitization. Testosterone also relaxed preparations with desensitized β-adrenoceptor. Therefore, testosterone modulates tracheal smooth muscle tone, facilitating bronchodilation caused by β(2)-adrenoceptor agonists which might be of pharmacological interest.
authors.affiliation: Farmacología, Departamento de Medicina, Universidad de Oviedo, Oviedo, España.
authors.forename: Lorena
authors.initials: L
authors.lastname: Suárez
authors.forename: María
authors.initials: M
authors.lastname: Pipa
authors.forename: Javier
authors.initials: J
authors.lastname: Granda
authors.forename: Ana
authors.initials: A
authors.lastname: Coto
authors.forename: Javier
authors.initials: J
authors.lastname: Bordallo
authors.forename: Begoña
authors.initials: B
authors.lastname: Cantabrana
authors.forename: María José
authors.initials: MJ
authors.lastname: García de Boto
authors.forename: Manuel
authors.initials: M
authors.lastname: Sánchez
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000378:metabolism; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000420:Albuterol / Q000494:pharmacology*; D000818:Animals; D001980:Bronchi / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002217:Carbachol / Q000494:pharmacology; D002417:Cattle; D000242:Cyclic AMP / Q000378:metabolism; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D005485:Flutamide / Q000494:pharmacology; D066298:In Vitro Techniques; D009126:Muscle Relaxation / Q000187:drug effects*; D009129:Muscle Tonus / Q000187:drug effects; D009130:Muscle, Smooth / Q000166:cytology / Q000187:drug effects; D011433:Propranolol / Q000494:pharmacology; D018343:Receptors, Adrenergic, beta-2 / Q000378:metabolism; D013739:Testosterone / Q000494:pharmacology*; D014132:Trachea / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
chemical_list: D000319:Adrenergic beta-Antagonists; D018343:Receptors, Adrenergic, beta-2; D013739:Testosterone; D005485:Flutamide; D002217:Carbachol; D011433:Propranolol; D000242:Cyclic AMP; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D000420:Albuterol