This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Messer, H.H. Articles by Ophaug, R.H. Search for Related Content PubMed PubMed Citation Articles by Messer, H.H. Articles by Ophaug, R.H. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB CIMETIDINE HYDROCHLORIC ACID PENTAGASTRIN SODIUM SODIUM BICARBONATE SODIUM FLUORIDE Social Bookmarking                         What's this?

Influence of Gastric Acidity on Fluoride Absorption in Rats

School of Dentistry, University of Minnesota, Minneapolis, Minnesota 55455

R.H. Ophaug

School of Dentistry, University of Minnesota, Minneapolis, Minnesota 55455

The rate of F absorption from the stomach is pH-dependent, with greater absorption at low pH. Since the rate of absorption is also strongly influenced by the rapidity of gastric emptying, we have compared the relative importance of gastric acidity and gastric emptying in overall F absorption. Male rats (350 g, n = 85) were pre-treated with cimetidine (to inhibit gastric acid secretion) or pentagastrin (to stimulate gastric acid secretion) or were untreated controls, and given 50 µg F by stomach intubation. The pH of the F-containing solution was varied in the cimetidine-pre-treated group (pH 1.5, 5.5, 8.5), and was 5.5 for the control and pentagastrin-pre-treated groups. Gastric emptying was measured by addition of 14C polyethylene glycol to the F solution as an unabsorbed marker of fluid movement. F absorption was measured after 10, 20, and 40 min. The rate of gastric emptying was unaffected by pre-treatment or pH of the intubating solution. Initially, F absorption was greatest at low pH. After 40 min, absorption was comparable in all groups, averaging approximately 70% of the initial dose. The extent of absorption from the stomach was inversely related to pH, but increased absorption from the small intestine compensated for the low gastric absorption at high pH.

REFERENCES

• Hoegerle ML, Winne D. (1983). Drug absorption by the rat jejunum perfused in situ. Dissociation from the pH-partition theory and the role of microclimate pH and unstirred layer. Arch Pharmacol 322:249-255.[CrossRef]
• Jackson MJ, Tai C.-Y, Steane JE (1981). Weak electrolyte permeation in alimentary epithelia. Am J Physiol 240:G191-198.[Medline] [Order article via Infotrieve]
• Lau HK, Ogle CW ( 1981). The influence of cimetidine, a histamine H2-receptor antagonist, on the gastric effects of reserpine in rats. Eur J Pharmacol 70:139-148.[CrossRef][Medline] [Order article via Infotrieve]
• Messer HH, Ophaug RH (1991). Effect of delayed gastric emptying on fluoride absorption in the rat. Biol Trace Element Res 31:305-315.[CrossRef][Medline] [Order article via Infotrieve]
• Nopakun J., Messer HH (1990). Mechanism of fluoride absorption from the rat small intestine. Nutr Res 10:771-780.[CrossRef]
• Nopakun J., Messer HH, Voller V. (1989). Fluoride absorption from the gastrointestinal tract of rats. J Nutr 119:1411-1417.[Abstract/Free Full Text]
• Ross IN, Bahari Hmm, Turnberg LA (1981). The pH gradient across mucus adherent to rat fundic mucosa in vivo and the effect of potential damaging agents. Gastroenterology 81:713-718.[Medline] [Order article via Infotrieve]
• Taylor JM, Gardner DE, Scott JK, Maynard EA, Downs WL, Smith F., Hodge HC (1961). Toxic effects of fluoride on the rat kidney. Toxicol Appl Pharmacol 3:290-314.[CrossRef][Medline] [Order article via Infotrieve]
• Whitford GM (1983). Physiological determinants of plasma fluoride concentrations. In: Shupe J, editor. Fluorides. Effects on vegetation, animals and humans. Utah: Paragon Press, 167-182.
• Whitford GM (1989). The metabolism and toxicity of fluoride. Monogr Oral Sci 13:1-158.[Medline] [Order article via Infotrieve]
• Whitford GM, Pashley DH (1984). Fluoride absorption: the influence of gastric acidity. Calcif Tissue Int 36:302-307.[CrossRef][Medline] [Order article via Infotrieve]
• Whitford GM, Pashley DH, Stringer GI (1976). Fluoride renal clearance: a pH-dependent event. Am J Physiol 230:527-532.[Abstract/Free Full Text]

Journal of Dental Research, Vol. 72, No. 3, 619-622 (1993)
DOI: 10.1177/00220345930720031101


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				X. Chen and G.M. Whitford Lack of Significant Effect of Coffee and Caffeine on Fluoride Metabolism in Rats Journal of Dental Research, June 1, 1994; 73(6): 1173 - 1179. [Abstract] [PDF]

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Messer, H.H. Articles by Ophaug, R.H. Search for Related Content PubMed PubMed Citation Articles by Messer, H.H. Articles by Ophaug, R.H. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB CIMETIDINE HYDROCHLORIC ACID PENTAGASTRIN SODIUM SODIUM BICARBONATE SODIUM FLUORIDE Social Bookmarking                         What's this?