Figure 3.
Mineralocorticoid receptor (MR) knockout (KO) nearly abolishes amiloride-sensitive currents (ΔIami) in the connecting tubule (CNT)/cortical collecting duct (CCD) and substantially reduces ΔIami in the late distal convoluted tubule (DCT2)/CNT. Representative whole cell current traces are shown from the CNT/CCD (top traces) and DCT2/CNT (bottom traces) isolated from a female control mouse (A) and a male MR KO mouse (B). Black bars indicate the presence of amiloride (2 µM) in the bath solution; holding potential = −60 mV. Amiloride washout resulted in a gradual increase of the inward current to a plateau level. Reapplication of amiloride returned the current to its baseline level and was used to determine ΔIami.