Aluminum metabolism in rats: effects of vitamin D, dihydrotachysterol, 1,25-dihydroxyvitamin D and phosphate binders.
In order to study the effects of vitamin D on aluminium balance when different forms of vitamin D and phosphate binders are used simultaneously for therapeutic purposes, 30 Sprague-Dawley weanling rats, weighing 44-66 g, were randomly assigned to 5 groups: (A) control, (B) aluminum hydroxide, (C) dihydrotachysterol at 16 micrograms/kg/day, (D) 1,25-dihydroxyvitamin D at 16 ng/kg/day and (E) vitamin D at 2,000 IU/kg/day. Aluminum hydroxide (60 mg/kg/day) in the feed was provided to all except the control group. The vitamin D or metabolites were fed by stomach tube daily for a period of 10 days. At the end of the study, the mean (+/- SEM) serum aluminum concentration, as determined by flameless atomic absorption spectrophotometry, was 5.0 +/- 2.4 micrograms/l; there were no significant differences in these results between groups. During the last three days of the study, 24-hour urine and stool collections were made with the usual precautions against trace mineral contamination. The means (+/- SEM) of aluminum balances for groups A, B, C, D and E were -388 +/- 261, 1,121 +/- 331; 2,316 +/- 304; 2,387 +/- 245, and 1,968 +/- 337 micrograms/day, respectively. We conclude that at therapeutic doses of aluminum hydroxide and vitamin D or its metabolites, hyperaluminemia was not observed. However, the positive aluminum balances imply retention, and the use of vitamin D, especially its potent metabolites dihydrotachysterol and 1,25-dihydroxyvitamin D, intensified this risk.
Chan
J C
JC
Department of Pediatrics, Virginia Commonwealth University's Medical College of Virginia, Richmond.
Jacob
M
M
Brown
S
S
Savory
J
J
Wills
M R
MR
D000535:Aluminum / Q000378:metabolism*; D000536:Aluminum Hydroxide / Q000378:metabolism; D000818:Animals; D002117:Calcitriol / Q000494:pharmacology*; D004097:Dihydrotachysterol / Q000494:pharmacology*; D004347:Drug Interactions; D005243:Feces / Q000032:analysis; D010710:Phosphates / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D014807:Vitamin D / Q000494:pharmacology*
D010710:Phosphates; D014807:Vitamin D; D000536:Aluminum Hydroxide; D000535:Aluminum; D002117:Calcitriol; D004097:Dihydrotachysterol