Inorganic saliva composition Oral cavity Duct Acinus Interstitium HCO CI-K+Na+ Final saliva(mM) unstimulated stimulated Primary saliva(mM) Interstitium(mM) Na+ 3 45 Na146 Na+143 K 25 21 K 4 K+ 4 cI- 24 40 C102 C109 HCO 3 26 HCO28 HCO 28 Pco2 4.5 4.5(kPa) Pco2 6(kPa) Pco2 6 (kPa) pH 6.5 7.5 protein 2.0 2.5(mg/ml) Inorganic saliva composition