BKCa、SK3、TREK-1钾离子通道在晚孕大鼠子宫中的表达及功能研究

目的:探讨大电导钙激活钾通道(BKCa)、小电导钙激活钾通道(SK3)以及双孔钾离子通道(TREK-1)在非孕和晚孕大鼠子宫中的表达,以及对子宫舒缩功能的影响。方法:将SD大鼠分为非孕组(NP)和晚孕组(孕19天,LP),采用Western blot法和q PCR法检测非孕和晚孕大鼠子宫组织中3种收缩相关钾离子通道(BKCa、SK3、TREK-1)蛋白和基因表达水平。利用等长收缩实验,观察比较两组子宫肌条在缩宫素诱导下的收缩能力变化以及TREK-1通道抑制剂对晚孕组子宫肌条收缩能力的影响。结果:与非孕组比较,晚孕组子宫组织中3种收缩相关钾离子通道(BKCa、SK3、TREK-1)蛋白表达水平和基因表达水平显著提高(P0.05),晚孕组肌条在缩宫素诱导下的收缩力显著降低(P0.05)。TREK-1通道抑制剂L-甲硫氨酸可显著提高晚孕组子宫肌条收缩能力(P0.05)。结论:晚孕子宫静息状态的维持与BKCa、SK3以及TREK-1通道表达密切相关,TREK-1通道可能通过调节子宫收缩能力参与分娩发动。

Expression and function of contraction-associated potassium channels in late-pregnant rat uterus

Objective:To investigate the expression of contraction-associated potassium channels in late-pregnant rat uterus and its influence on the uterine contraction.Method:Uteri from non-pregnant(NP) and late-pregnant(LP) was isolated and myometrium strips were prepared for measurement of isometric contraction and potassium channels expression and activity using qPCR and Western blot.Result:Western blot and qPCR analysis demonstrated increased protein amount and mRNA expression in late-pregnant uterus compared with non-pregnancy.Oxytocin caused concentration-dependent contraction of myometrium strips that was reduced in late-pregnant rats compared with non-pregnancy.TREK-1 channel inhibitor L-Methionone caused increased contraction after maximum oxytocin pretreatment in late-pregnant rats.Conclusion:The expression of contraction-associated potassium channels BKCa,SK3 and TREK-1 contributes to the quiescent maintenance of late-pregnant.The uterine contraction regulated by TREK-1 channels during pregnancy may be associated with the onset of delivery.