title: Demonstration of the rapid action of pure crystalline 1 alpha-hydroxy vitamin D3 and 1 alpha,25-dihydroxy vitamin D3 on intestinal calcium uptake.
abstract: The biological effects of crystalline 1alpha-hydroxyvitamin D3 and crystalline 1alpha,25-dihydroxyvitamin D3 have been compared on the intestinal uptake of calcium-45 by everted duodenal gut sacs from rachitic rats. Peak calcium-45 uptake was observed 1 hr after intravenous administration and both crystalline vitamin D2 analogs were of comparable potency. The rapid onset of calcium-45 uptake and the rapid attainment of maximal calcium-45 transport suggests a direct effect of these crystalline analogs on the mucosal membranes of the intestinal cell.
mesh_terms: D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D002132:Calcium Radioisotopes; D004100:Dihydroxycholecalciferols / Q000494:pharmacology*; D004386:Duodenum / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006887:Hydroxycholecalciferols / Q000494:pharmacology*; D007408:Intestinal Absorption / Q000187:drug effects; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051381:Rats; D012279:Rickets / Q000378:metabolism
chemical_list: D002132:Calcium Radioisotopes; D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols; D002118:Calcium