EFFECTS OF AGE ON GASTRIC ALKALINE AND NONPARIETAL FLUID SECRETION INHUMANS

Little is known about the effect of age on gastric alkaline and nonpar ietal secretion. Using a previously validated technique, we prospectiv ely measured gastric HCO3- and nonparietal volume secretion, as well a s secretion of H+, Na+, K+, and Cl-, in 114 healthy human beings over a wide age range(18-82 years). Each subject had normal oxyntic mucosal histology, was on no medication known to affect gastric secretion, an d was studied under both basal (fasting) conditions and following stim ulation of gastric H+ secretion by pentagastrin. There was a significa nt (p < 0.05) decline in gastric HCO3-, Na+, and nonparietal fluid sec retion with advancing age, but not in H+, K+, Cl- or parietal fluid se cretion. As a consequence of reduced gastric HCO3- and nonparietal flu id secretion, mean H+ concentrations in gastric juice increased signif icantly with advancing age. Thus, in healthy subjects with normal gast ric histology, advancing age was associated with a significant decline in gastric HCO3-, Na+, and nonparietal fluid secretion, resulting in an increase in gastric acidity (H+ concentration).