Effects of hyperthyroidism on the electrophysiological characteristics between atrium and gap junction between atrium and pulmonary vein / 中华急诊医学杂志

ABSTRACT

Objective To investigate the effects of hyperthyroidism on the electrophysiological characteristics of atrium and gap junction between atrium and pulmonary vein.Methods Twenty-four rabbits were randomly divided into control group and hyperthyroid group.Atrium and pulmonary vein were dissected after the atrial effective refractory period (AERP)was measured.Connexin 43(Cx43)and Counexin 40(Cx40)protein and mRNA were determined by Western blot and semi-quantitative reverse transcription-polymerase chain reaction,respectively.Results In comparison with control group,AERP and rate adaption of AERP in hyperthyroid group were significantly shorter than that of control group( P＜0.01).The concentration of Cx43 protein in hyperthyroid group was significantly higher than that of control group,but Cx40 protein was significantly lower than that of control group(P＜0.05).The expression of Cx43 mRNA in atrium and pulmonary vein was found to be up-regulated in hyperthyroid group as compared with that of control group(P＜0.01). With the level of Cx40 mRNA,there was no significant difference between two groups.Conclusion Thyroid hormone could lead to remodeling of both atrial electrophysiology and gap junction between atrium and pulmonary vein.