Fig. 7.

Schematic representation of the impact of angiotensin II (ANG II) on Na⁺ and K⁺ transport in the distal nephron. The proposed chain of events is illustrated, connecting direct ANG II activation of epithelial Na⁺ channel (ENaC) (1) with indirect activation of Na⁺-Cl⁻ cotransporter (NCC) phosphorylation mediated by coupling of Na⁺ reabsorption (2) with K⁺ secretion (3) in the connecting tubule (CNT) and cortical collecting duct (CCD) driving urinary K⁺ loss (4), which activates NCC via phosphorylation (NCC-P) (5) to minimize Na⁺ delivery to ENaC to blunt further K⁺ loss. AT1R, ANG II type 1 receptor; BK, large-conductance Ca²⁺-activated K⁺ channel; DCT, distal convoluted tubule; ROMK, renal outer medullary K⁺ channel.