Paracrine communication between different parts of the renal tubule is increasingly recognized as an important determinant of renal function. Previous studies have shown that changes in dietary acid-base load can reverse the direction of apical α-ketoglutarate (αKG) transport in the proximal tubule and Henle’s loop from reabsorption (acid load) to secretion (base load). Here we show that the resulting changes in the luminal concentrations of αKG are sensed by the αKG receptor OXGR1 expressed in the type B and non-A–non-B intercalated cells of the connecting tubule (CNT) and the cortical collecting duct (CCD). The addition of 1 mM αKG to the tubular lumen strongly stimulated Cl–-dependent HCO3– secretion and electroneutral transepithelial NaCl reabsorption in microperfused CCDs of wild-type mice but not
Natsuko Tokonami, Luciana Morla, Gabriel Centeno, David Mordasini, Suresh Krishna Ramakrishnan, Svetlana Nikolaeva, Carsten A. Wagner, Olivier Bonny, Pascal Houillier, Alain Doucet, Dmitri Firsov
OXGR1 is expressed in type B and non-A–non-B intercalated cells of the CNT and the CCD.