title: Evidence for aqueous soluble vitamin D-like substances in the calcinogenic plant, Tristetum flavescens.
abstract: A crude aqueous extract of the leaves of T. flavescens when administered orally to vitamin D-deficient chicks produced significant increases in plasma phosphate but had little effect on plasma calcium. When chicks, fed a high strontium diet to inhibit endogenous 1,25 (OH)2 vitamin D3 production and intestinal calcium transport, were dosed with the extract or synthetic 1,25 (OH)2D345Ca absorption from the duodenum in vivo was stimulated, whereas vitamin D3 was ineffective. Partial purification of the crude extract on a Sephadex GH25 column yielded two factors, one of which mimicked 1,25 (OH)2D3 activity in chicks fed the high strontium diet while the other produced a significant increase in plasma phosphate. The presence of these substances, together with previously demonstrated organic solvent soluble vitamin D-type activity, may account for the calcinogenic nature of the plant.
mesh_terms: D000818:Animals; D002114:Calcinosis / Q000139:chemically induced*; D002117:Calcitriol / Q000032:analysis; D002118:Calcium / Q000097:blood; D002645:Chickens; D004032:Diet; D008297:Male; D010710:Phosphates / Q000097:blood; D010936:Plant Extracts / Q000494:pharmacology; D010947:Plants, Toxic / Q000032:analysis*; D012995:Solubility; D013324:Strontium / Q000494:pharmacology; D014807:Vitamin D / Q000032:analysis*; D014867:Water
chemical_list: D010710:Phosphates; D010936:Plant Extracts; D014867:Water; D014807:Vitamin D; D002117:Calcitriol; D002118:Calcium; D013324:Strontium