Fig. 5.

Inward-rectifier K⁺ (K_IR) channel currents and functional role in isolated bladder arteriolar smooth muscle cells. A: representative traces of whole cell currents from isolated bladder arterioles in the absence (gray line) or presence (red line) of 100 µM BaCl₂. Bladder arteriole myocytes exhibit a Ba²⁺-sensitive, inward-rectifying current (black line). B: summary graph of Ba²⁺-sensitive inward currents (at −140 mV and −100 mV membrane potentials) in isolated smooth muscle cells from bladder feed arterioles (n = 6 cells from N = 6 mice). C: representative tracings of bladder feed arteriolar responses to BaCl₂ (100 µM). D: summary graph showing that BaCl₂ caused a concentration-dependent constriction of bladder arterioles. N = 4–5.