Developmental changes of BK Ca channels depend on differentiation status in cultured podocytes

The podocyte is a remarkable cell type, which encases the capillaries of the kidney glomerulus. Podocytes are of keen interests because of their key roles in kidney development and disease. Large-conductance Ca 2+ -activated K + channels (BK Ca channels) are important ion channels located in podocytes and play the essential role in regulating calcium homeostasis cell signaling. In this research, we studied the undergoing developmental changes of BK Ca channels and their contribution to functional maturation of podocytes. Our results showed that the distribution of BK Ca channels changed with the maturity of differentiation in a conditionally immortalized mouse podocyte cell line. Additionally, the increase of BK Ca channel protein expression was detected by immunofluorescence staining with confocal microscopy in podocytes, which was consistent with the increase in the current density of BK Ca channels examined by whole-cell patch-clamp technique. Our results suggested that the developmental changes of BK Ca channels may help podocytes adapt to changes in pressure gradients occurring in physiological conditions. Those findings may have implications for understanding the physiology and development of kidney and will also serve as a baseline for future studies designed to investigate developmental changes of ion channel expression in podocytes.