Expression And Regulation Of Large-conductance Calcium-sensitive Potassium Channels In Human Term Myometrium

In this study the expression levels of large-conductance calcium-sensitive potassium channel (BKCa) protein in human myometrium tissues were measured by Western blot analysis. Human myometrial cells were prepared by primary cell culture method. Immunocytochemistry of smooth muscle actin (SMA) was used to identify their characteristic. Reverse transcription real-time PCR and Western blot analysis were used to investigate the effect of CRH on the expression of BKCa of the primary uterus myometrial cells. The results were as follows : Expression of BKCa channel protein in lower segment myometrium of term non-labor group was higher than that of term labor. Myometrial cells prepared by enzymatic digestion with collagenase or tissue culture displayed positive immunocytochemistry of SMA and preserved their contraction-associated protein receptors. CRH of physiological concentrations (10-9 mol/L to 10-8mol/L ) up-regulated the expression of BKCa channelαsubunit mRNA and protein, which may be mediated through CRH-R1 and CRH-R2 receptors .