title: Effects of amiodarone on lung tissue mechanics and parenchyma remodeling.
abstract: We studied the results of chronic oral administration of amiodarone on in vitro lung tissue mechanics, light and electron microscopy. Fifteen Wistar male rats were divided into three groups. In control (CTRL) group animals received saline (0.5 mL/day). In amiodarone (AMIO) groups, amiodarone was administered by gavage at a dose of 175 mg/kg 5 days per week for 6 (6AMIO) or 12 weeks (12AMIO). Lung tissue strips were analyzed 24h after the last drug administration. Tissue resistance and elastance were higher in 6AMIO and 12AMIO than in CTRL, while hysteresivity was similar in all groups. Total amount of collagen fibers in lung parenchyma increased progressively with the time course of the lesion. However, at 6 weeks there was an increase in the amount of type III collagen fibers, while in 12AMIO mainly type I collagen fibers were found. In our study amiodarone increased lung tissue impedance that was accompanied by matrix remodeling and lesion of type II pneumocytes.
authors.affiliation: Laboratory of Respiration Physiology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Ilha do Fundão, 21949-900 Rio de Janeiro, Brazil.
authors.forename: Flavia B
authors.initials: FB
authors.lastname: Santos
authors.forename: Cristiane S N B
authors.initials: CS
authors.lastname: Garcia
authors.forename: Débora G
authors.initials: DG
authors.lastname: Xisto
authors.forename: Elnara M
authors.initials: EM
authors.lastname: Negri
authors.forename: Vera L
authors.initials: VL
authors.lastname: Capelozzi
authors.forename: Débora S
authors.initials: DS
authors.lastname: Faffe
authors.forename: Patricia R M
authors.initials: PR
authors.lastname: Rocco
authors.forename: Walter A
authors.initials: WA
authors.lastname: Zin
mesh_terms: D000638:Amiodarone / Q000009:adverse effects*; D000704:Analysis of Variance; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects*; D024042:Collagen Type I / Q000187:drug effects; D024061:Collagen Type III / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004548:Elasticity / Q000187:drug effects; D005109:Extracellular Matrix / Q000187:drug effects*; D066298:In Vitro Techniques; D008168:Lung / Q000187:drug effects* / Q000648:ultrastructure; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015656:Respiratory Mechanics / Q000187:drug effects*; D018709:Statistics, Nonparametric; D013997:Time Factors
chemical_list: D000889:Anti-Arrhythmia Agents; D024042:Collagen Type I; D024061:Collagen Type III; D000638:Amiodarone