Gastric HCO3- secretion: relationship with Na+ secretion and effect of acetazolamide in humans.
We examined the relationship between gastric HCO3- and Na+ secretion under fasting and sham-fed conditions in nine healthy men and also evaluated the effect of the carbonic anhydrase inhibitor acetazolamide on gastric secretion of HCO3- and Na+. Secretion of H+, K+, and Cl- were also measured. Gastric HCO3- secretion rates under fasting and sham-fed conditions closely paralleled Na+ secretion rates. A maximally tolerated intravenous dose (10 mg/kg) of acetazolamide significantly inhibited H+, Cl- and K+ secretion but did not significantly affect Na+ or HCO3- secretion. Thus the gastric mucosa secretes HCO3- and Na+ in parallel in humans both under fasting and sham-fed conditions. Relative to parietal secretion of HCl, nonparietal secretion of HCO3- and Na+ is resistant to carbonic anhydrase inhibition.
Feldman
M
M
Medical Service, Department of Veterans Affairs Medical Center, Dallas, Texas.
Goldschmiedt
M
M
D000086:Acetazolamide / Q000494:pharmacology*; D000328:Adult; D001639:Bicarbonates / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D007477:Ions; D008297:Male; D008722:Methods; D012964:Sodium / Q000378:metabolism*
D001639:Bicarbonates; D007477:Ions; D012964:Sodium; D000086:Acetazolamide