Effects of age on gastric alkaline and nonparietal fluid secretion in humans.
Little is known about the effect of age on gastric alkaline and nonparietal secretion. Using a previously validated technique, we prospectively measured gastric HCO3- and nonparietal volume secretion, as well as 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, and was studied under both basal (fasting) conditions and following stimulation of gastric H+ secretion by pentagastrin. There was a significant (p < 0.05) decline in gastric HCO3-, Na+, and nonparietal fluid secretion with advancing age, but not in H+, K+, Cl- or parietal fluid secretion. As a consequence of reduced gastric HCO3- and nonparietal fluid secretion, mean H+ concentrations in gastric juice increased significantly with advancing age. Thus, in healthy subjects with normal gastric 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).
Feldman
M
M
Department of Internal Medicine, Veterans Affairs Medical Center, Dallas, TX 75216, USA. feldman, mark@dallas.va.gov
Cryer
B
B
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D000468:Alkalies / Q000378:metabolism*; D001639:Bicarbonates / Q000378:metabolism; D001826:Body Fluids / Q000378:metabolism*; D004573:Electrolytes / Q000378:metabolism; D005260:Female; D005750:Gastric Juice / Q000378:metabolism; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D010418:Pentagastrin / Q000494:pharmacology; D013270:Stomach / Q000187:drug effects
D000468:Alkalies; D001639:Bicarbonates; D004573:Electrolytes; D010418:Pentagastrin