Angiotensin II-Type-1a Receptor and Renal K + Wasting during Overnight Low-Na + Intake.

Key Points: Angiotensin II–type-1a-receptor in the distal convoluted tubule (DCT) plays a role in regulating sodium transport in the DCT. Angiotensin II–type-1a-receptor in the DCT plays a role in maintaining potassium homeostasis during sodium restriction.

Background: Chronic angiotensin II perfusion stimulates Kir4.

mTORc2 in Distal Convoluted Tubule and Renal K + Excretion during High Dietary K + Intake.

Key Points: High K stimulates mechanistic target of rapamycin complex 2 (mTORc2) in the distal convoluted tubule (DCT). Inhibition of mTORc2 decreased the basolateral Kir4.1/Kir5.

Role of Angiotensin II Type 1a Receptor (AT1aR) of Renal Tubules in Regulating Inwardly Rectifying Potassium Channels 4.2 (Kir4.2), Kir4.1, and Epithelial Na Channel (ENaC).

Background: Kir4.2 and Kir4.1 play a role in regulating membrane transport in the proximal tubule (PT) and in the distal-convoluted-tubule (DCT), respectively.

Calcineurin inhibitors stimulate Kir4.1/Kir5.1 of the distal convoluted tubule to increase NaCl cotransporter.

We examine whether calcineurin or protein phosphatase 2B (PP2B) regulates the basolateral inwardly rectifying potassium channel Kir4.1/Kir5.1 in the distal convoluted tubule (DCT).

Role of inwardly rectifying K+ channel 5.1 (Kir5.1) in the regulation of renal membrane transport.

Purpose Of Review: Kir5.1 interacts with Kir4.2 in proximal tubule and with Kir4.

ROMK channels are inhibited in the aldosterone-sensitive distal nephron of renal tubule Nedd4-2-deficient mice.

We used whole cell recording to examine the renal outer medullary K channel (ROMK or Kir1.1) and epithelial Na channel (ENaC) in the late distal convoluted tubule (DCT2)/initial connecting tubule (CNT) and in the cortical collecting duct (CCD) of kidney tubule-specific neural precursor cell-expressed developmentally downregulated protein 4-2 (Nedd4-2) knockout mice (Ks-Nedd4-2 KO) and floxed neural precursor cell-expressed developmentally downregulated 4-like () mice (control). Tertiapin Q (TPNQ)-sensitive K currents (ROMK) were smaller in both the DCT2/CNT and CCD of Ks-Nedd4-2 KO mice on a normal diet than in control mice.