For | Against |
---|---|
High rate of HCO3 − loss from or gain to fluids perfused through the ventricles | Little or no change in total CO2 (almost all of which is HCO3 −) in the brain in response to altered [HCO3 −] in plasma |
Rapid, easily seen changes in pH (measured by electrodes applied to the brain surface or microelectrodes within the parenchyma) in response to changes in [HCO3 −]plasma | Little or no change in pH (measured by electrodes applied to the brain surface or microelectrodes within the parenchyma) in response to changes in [HCO3 −]plasma |
Measurable first-pass extraction of H11CO3 − from blood | No change in intracellular pH measured using 31P-NMR over an hour following decrease in plasma [HCO3 −] |
Acute changes in ventilation rate (after denervation of peripheral chemoreceptors) when [HCO3 −]plasma is changed at constant pCO2 | low measured permeability to Cl− determined using radiotracers |