“Now, using perfused rat CB (n=6) in the … normal extracellular [Ca2+] we show that chemosensory response to CO (pCO approximately 550 Torr) in normoxic (pO2 approximately 100 Torr) normocapnia (pCO2 … Torr, pH approximately 7.4) is completely but reversibly inhibited by Cd2+ (200 microM), a … Ca2+ channel blocker.”