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]