Increased placental concentrations of 25-hydroxyvitamin D3 and 24,25-dihydroxyvitamin D3 in pregnant rats treated with human chorionic gonadotropin.
Pregnant rats were injected intrajugularly with 2500 i.u. human chorionic gonadotropin (HCG) toward the end of gestation (days 18-19) and 7.0 pmoles of tritiated 25-hydroxyvitamin D3 [( 3H]25(OH)D3) the following day. They were sacrificed ten to 24 hours later. [3H]25(OH)D3 and the in vivo produced [3H]24,25-dihydroxyvitamin D3 [( 3H]24,25(OH)2D3) in lipid extracts from maternal serum, kidneys, placenta and fetal tissues were separated by Sephadex LH-20 chromatography, and high performance liquid chromatography (HPLC). HCG treatment of pregnant rats increased significantly 25(OH)D3 levels in the placenta and kidneys and 24,25(OH)2D3 level in the placenta. Fetal metabolites levels were unaffected by HCG treatment. Serum and kidney levels of 25(OH)D3 and 24,25(OH)2D3 in pregnant rats were significantly lower than in non-pregnant rats. Serum and kidney levels of both metabolites in non-pregnant female rats treated with HCG did not differ from the untreated controls. HCG may, therefore, be involved in regulation of fetoplacental vitamin D metabolism.
D000818:Animals; D002112:Calcifediol / Q000378:metabolism*; D002117:Calcitriol / Q000378:metabolism*; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D005260:Female; D005333:Fetus; D007668:Kidney / Q000378:metabolism; D010920:Placenta / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D014018:Tissue Distribution; D014316:Tritium
D006063:Chorionic Gonadotropin; D014316:Tritium; D002117:Calcitriol; D002112:Calcifediol