English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Oseltamivir has been shown to prolong the atrial conduction time and effective refractory period, and to suppress the onset of burst pacing-induced atrial fibrillation  in vitro . To better predict its potential clinical benefit as an anti-atrial fibrillatory drug, we performed translational studies by assessing  in vivo  anti-atrial fibrillatory effect along with  in vivo  and  in vitro  electropharmacological analyses. Oseltamivir in intravenous doses of 3 (n = 6) and 30 mg/kg (n = 7) was administered in conscious state to the persistent atrial fibrillation model dogs to confirm its anti-atrial fibrillatory action. The model was prepared by tachypacing to the atria of chronic atrioventricular block dogs for > 6 weeks. Next, oseltamivir in doses of 0.3, 3 and 30 mg/kg was intravenously administered to the halothane-anesthetized intact dogs to analyze its  in vivo  electrophysiological actions (n = 4). Finally, its  in vitro  effects of 10–1,000 μM on I K,ACh , I Kur , I Kr , I Na  and I CaL  were analyzed by using cell lines stably expressing Kir3.1/3.4, K V 1.5, hERG, Na V 1.5 or Ca V 1.2, respectively (n = 3 for I K,ACh  and I Kr  or n = 6 for I Kr , I Na  and I CaL ). Oseltamivir in doses of 3 and 30 mg/kg terminated the atrial fibrillation in 1 out of 6 and in 6 out of 7 atrial fibrillation model dogs, respectively without inducing any lethal ventricular arrhythmia. Its 3 and 30 mg/kg delayed inter-atrial conduction in a frequency-dependent manner, whereas they prolonged atrial effective refractory period in a reverse frequency-dependent manner in the intact dogs. The current assay indicated that IC 50  values for I K,ACh  and I Kr  were 160 and 231 μM, respectively, but 1,000 µM inhibited I Na , I CaL  and I Kur  by 22, 19 and 13%, respectively. The extent of I Na  blockade was enhanced at faster beating rate and more depolarized resting membrane potential. Oseltamivir effectively terminated the persistent atrial fibrillation, which may be largely due to the prolongation of the atrial effective refractory period and inter-atrial conduction time induced by I K,ACh  and I Kr  inhibitions along with I Na  suppression. Thus, oseltamivir can exert a powerful anti-atrial fibrillatory action through its ideal multi-channel blocking property; and oseltamivir would become a promising seed compound for developing efficacious and safe anti-atrial fibrillatory drugs.

Translational Studies on Anti-Atrial Fibrillatory Action of Oseltamivir by its in vivo and in vitro Electropharmacological Analyses