The Paradox of Dopamine and Angiotensin II-Mediated Na+, K+-ATPase Regulation in Renal Proximal Tubules

Accumulated studies reported that the natruretic dopamine (DA) and the anti-natruretic angiotensin II (Ang II) represent an important mechanism to regulate renal Na+ and water excretion through intracellular secondary messengers to inhibit or activate renal proximal tubule (PT) Na+,K+-ATPase (NKA). The antagonistic actions were mediated by the phosphorylation of different position of NKA alpha(1)-subunit and different Pals-associated tight junction protein (PATJ) PDZ domains, the different protein kinase C (PKC) isoforms (PKC-beta, PKC-zeta), the common adenylyl cyclase (AC) pathway, and the crosstalk and balance between DA and Ang II to NKA regulation. Besides, Ang II-mediated NKA modulation has bi-phasic effects.