Mechanosensitive Channel Currents Recorded in Rat Brain Microvascular Endothelial Cells with Whole-cell Mode

CHANG Xiao-Fei, ZENG Yan-Jun^*, HU Jin-Lin¹
( Biomedical Engineering Center, Beijing Polytechnic University, Beijing 100022, China； ¹Microcirculation Lab, Chinese PLA General Hospital, Beijing 100853, China )

Abstract    Using the whole-cell patch-clamp technique, delayed outward currents were recorded in rat brain microvascular endothelial cells(RBMECs), which were nearly completely inhibited by extracellular TEA-Cl at a concentration of 20 mmol/L. Whole-cell currents were elicited by 2 100 ms depolarizing voltage pulses applied every 7 s between -100 mV to +90 mV, with 10 mV increment, from a holding potential of -100 mV. The currents were similar with delayed rectified K⁺ currents (IKv)which were inhibited in a concentration-dependent manner by both application of TEA-Cl, with an IC₅₀ approximately 2.0 mmol/L. In the presence of mechanical force, outward currents were increased in amplitude as compared with controls. These mechanical force-induced currents were also defined as IKv, which were different from previous described mechanosensitive currents induced by mechanical force with characteristic of inward rectifier.
Key words    mechanosensetive ion channels；rat brain microvascular endothelial cells (RBMECs)；whole-cell patch-clamp technique

^*Corresponding author：Tel,86-10-67391685；Fax：86-10-67392297；e-mail,[email protected]