Premium
THE ROLE OF EPITHELIUM, THE EXTRACELLULAR Ca++ AND NO IN THE DOG TRACHEAL SMOOTH MUSCLE CONSTRICTIVE RESPONSE TO Pb ACETATE
Author(s) -
Jakupaj Muharrem,
Neziri Burim,
Krasniqi Avdyl
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.5.lb41
Subject(s) - lead acetate , extracellular , chemistry , epithelium , nitric oxide , cadmium acetate , smooth muscle , medicine , endocrinology , biophysics , biochemistry , biology , pathology , toxicity , organic chemistry , cadmium
Epithelial cells play an important role in the regulation of the muscle tone of the airway smooth muscle (ASM). This is mediated by the local release of active substances. Thus, the constriction and its continuation and the relaxation depend on the integrity of the airway epithelium, on the functional integrity of the epithelial cells and on the signals that are triggered by the activation of these cells. We studied the role of epithelial cells, nitric oxide (NO) and extracellular Ca++ on the constrictive response of the tracheal smooth muscle (TSM) induced by lead acetate (Pb‐acetate). The results showed that Pb‐acetate in concentrations 0.00026 – 2.6 mM/L invariably caused contraction of TSM. The constrictive effect of Pb‐acetate was significantly increased with epithelial removal prior to Pb‐acetate exposure. Prior incubation of the TSM with bradykinine 0.4 mM resulted with marked attenuation of the constrictive effects of Pb‐acetate. Removal of Ca+ from the bathing medium resulted with significant decrease in TSM constrictive response to Pb‐acetate. The results showed that the constrictive response of TSM caused be Pb‐acetate is modulated by the intact epithelium, NO and extracellular Ca++.