Novel Concepts in Nephron Sodium Transport: A Physiological and Clinical Perspective

The kidneys play a critical role in maintaining total body sodium (Na ) balance across a wide range of dietary intake, accomplished by a concerted effort involving multiple Na transporters along the nephron. Furthermore, nephron Na reabsorption and urinary Na excretion are closely linked to renal blood flow and glomerular filtration such that perturbations in either of them can modify Na transport along the nephron, ultimately resulting in hypertension and other Na -retentive states. In this article, we provide a brief physiological overview of nephron Na transport and illustrate clinical syndromes and therapeutic agents that affect Na transporter function. We highlight recent advances in kidney Na transport, particularly the role of immune cells, lymphatics, and interstitial Na in regulating Na reabsorption, the emergence of potassium (K ) as a regulator of Na transport, and the evolution of the nephron to modulate Na transport.