Maintaining K + balance on the low-Na + , high-K + diet.

A low-Na ⁺ , high-K ⁺ diet (LNaHK) is considered a healthier alternative to the "Western" high-Na ⁺ diet. Because the mechanism for K ⁺ secretion involves Na ⁺ reabsorptive exchange for secreted K ⁺ in the distal nephron, it is not understood how K ⁺ is eliminated with such low Na ⁺ intake. Animals on a LNaHK diet produce an alkaline load, high urinary flows, and markedly elevated plasma ANG II and aldosterone levels to maintain their K ⁺ balance. Recent studies have revealed a potential mechanism involving the actions of alkalosis, urinary flow, elevated ANG II, and aldosterone on two types of K ⁺ channels, renal outer medullary K ⁺ and large-conductance K ⁺ channels, located in principal and intercalated cells. Here, we review these recent advances.
(Copyright © 2016 the American Physiological Society.)