Activation of Inward Rectifier K⁺ Channel 2.1 by PDGF-BB in Rat Vascular Smooth Muscle Cells through Protein Kinase A

Figure 1

Effects of PDGF-BB on Kir2.x currents. (a) Original tracings illustrating currents determined in RASMCs. Membrane potential (E_m) was held at -80 mV, and pulse potentials were applied from -150 mV to 0 mV. (b) Arithmetic () of current-voltage relationship curves. (c)Arithmetic () of the current amplitude at -150 mV of Kir2.x currents in Ba²⁺; CON. vs. Ba²⁺; PDGF-BB vs. CON; PDGF-BB+Ba²⁺. vs. PDGF-BB. (d) The “O” and “C” indicate the opened and closed states of Kir2.x currents, respectively. (e) Ba²⁺ attenuated and PDGF-BB increased the NPo of Kir2.x currents (at +70 mV) by and ( vs. CON, ) compared to CON () ( vs. Ba²⁺, ), and PDGF-BB+Ba²⁺ was ( vs. PDGF-BB, ). (f) Time course of PDGF-BB action of Kir2.x currents. Averaged NPo plot (5 s bins) from five repeated perfusions of indicated compounds were normalized to control. CON means vascular smooth muscle cells without any drug intervention.

(a)

(b)

(c)

(d)

(e)

(f)