Effects of hypothermia combined with sevoflurane on expression of myocardial gap junction protein connexin 43 in isolated rabbit hearts / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of hypothermia combined with sevoflurane on expression of myocardial gap junction protein connexin 43 (Cx43) in isolated rabbit hearts.Methods Healthy adult rabbits of both sexes,weighing 1.5-2.0 kg,were sacrificed after anesthetization.The hearts were rapidly excised and perfused in a langendorff apparatus with K-H solution saturated with 95％ O2-5％ CO2 at 37 ℃ in a langendorff apparatus.Forty isolated hearts were randomly divided into 4 groups (n =10 each)control group (group C),hypothermia group (group H) and hypothermia combined with sevoflurane group (group HS).At 15 min of equilibration,the perfusion with K-H solution was continued at 37 ℃ in group C,K-H solution saturated with 2.4％ sevoflurane was perfused at 37 ℃ in group S,K-H solution was perfused at 30 ℃ in group H,and K-H solution saturated with 2.4％ sevoflurane was perfused at 30 ℃ in group HS.At 30 min of perfusion,myocardial specimens were obtained from the anterior wall of the left ventricle for detection of the expression of Cx43 in myocardial cells (by immunohistochemistry and Western blot).Results Compared with group C,Cx43 expression was downregualted in group H (P ＜ 0.05),and no significant change was found in Cx43 expression in S and HS groups (P ＞ 0.05).Cx43 levels distributed mainly in the intercalated disc in S and HS groups,and in H group the distribution of Cx43 levels in the intercalated disc was less,but the percentages of lateralized Cx43 were increased.Conclusion Sevofurane can inhibit hypothermia-induced down-regulation and distribution disturbance of myocardial Cx43 expression,which may be the mechanism by which sevofurane inhibits hypothermia-induced arrhythmia.