Expression of an electrically silent voltage-gated potassium channel in the human placenta

Abstract

Human placental expression of K_V9.3, a voltage-gated K channel linked to tissue oxygenation responses, has been suggested at the messenger RNA level but tissue localisation has not been described. We aimed to: (1) produce an antibody to human K_V9.3 and (2) assess channel expression and distribution in human placental tissue. We determined human placental protein expression and localisation using an antibody to K_V9.3. Antibody specificity was confirmed by Western blotting. Staining was observed in syncytiotrophoblast microvillous membrane, endothelial cells (in intermediate, stem villi and chorionic plate blood vessels) and vascular smooth muscle cells (large diameter vessels only) by immunohistochemistry. Expression was unchanged in tissue from women with small-for-gestational age babies. It was concluded that K_V9.3 is localised to human placental vascular tissues and syncytiotrophoblast.

Keywords::

• Human
• placenta
• potassium channel

Acknowledgements

The authors would like to acknowledge Ms Jemma Corcoran for technical assistance (Western Blotting).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

The research was performed at the Tommy's funded Maternal and Fetal Health Research Centre, Manchester, UK. Gregor Fyfe was funded by Action Medical Research.