Physiology General 7e2b88cf The tubuloglomerular feedback is mediated by: A Sensing of Na+ concentration in the macula densa B Sensing of HCO3 - concentration in macula densa C Sensing NaCl concentration in the macula densa D Opening up of voltage gated Na+ channels in afferent arteriole High-Yield Explanation Macula densa sense both Na+ and Cl- , but Cl- is more important.