"This demonstration of 'tubulo-glomerular feedback' therefore provided mechanistic insights into one of the fundamental homeostatic functions of the kidney—the ability to conserve salt and water. Adjusting filtered sodium load to match tubular reabsorptive capacity is essential to prevent excessive urinary sodium losses that would quickly result in cardiovascular collapse. Demonstration of this feedback loop between the tubular and glomerular portions of the same nepron provided a new dimension to understanding the nephron as a single, connected physiological unit" (Feehally et al, Landmark papers in nephrology [2013] 1.4, p. 9) With J. Schnermann, W. Nagel, M. Horster, and M. Wahl.