The influence of citrate, maltolate and fluoride on the gastrointestinal absorption of aluminum at a drinking water-relevant concentration: A Al-26 and C-14 study

摘要

The objectives were to test the null hypotheses that (1) citrate, maltolate, and fluoride do not significantly influence oral Al bioavailability. C-max or T-max at an Al dose relevant to drinking water exposure; and (2) Al citrate and maltolate are absorbed intact from the gastrointestinal tract. Male Fisher rats were given 1 ml of solution intra-gastrically containing 1 nCi Al-26 (65 nmol total Al) as the Al3+ ion, or as complexes with C-14-citrate, C-14-maltolate or fluoride, during concurrent Al-27 iv infusion. Blood was repeatedly collected for serum 26 At, total At and 14 C quantification. Absorption parameters were estimated using WinNonlin. At bioavailability, Cm and T a from the ion, citrate, maltolate, and fluoride were 0.29 +/- 0.11%, 0.61 +/- 0.31%, 0.50 +/- 0.25%, and 0.35 +/- 0.10%; 659 +/- 195, 1073 +/- 250, 881 +/- 356, and 880 +/- 1295 fg/ml; and 1.2 +/- 0.9, 1.0 +/- 1.1, 1.3 +/- 1.0, and 1.0 +/- 0.9 h (X +/- SD) respectively. Serum C-14 was similar to 100 times higher than Al-26. The results suggest a non-significant enhancement of oral At bioavailability by citrate and maltolate, some At complex dissociation in the GI tract, and less absorption of At than citrate or maltolate. The presence of citrate, maltolate and fluoride, at a similar molar concentration to At, would not be expected to greatly influence At absorption from drinking water. (c) 2008 Elsevier Inc. All rights reserved.