Effect of estrogen on vitamin D metabolism in tall girls.
To determine the effect of estrogen on vitamin D metabolism in pubertal girls, we studied 16 tall girls treated with a daily dose of 4-8 mg estradiol valerate to curtail excessive adult height. In all but one girl the plasma concentration of 1,25-dihydroxyvitamin D (1,25-(OH)2D) increased to values significantly higher than the corresponding pretreatment value (P less than 0.0005). The ratio of 24,25-dihydroxyvitamin D (24,25-(OH)2D) to 25-hydroxyvitamin D decreased in all girls (P less than 0.0005). The vitamin D binding protein (DBP) also increased significantly after estrogen (P less than 0.025), and there was a significant positive correlation between the plasma concentration of 1,25-(OH)2D and DBP (r = 0.66; P less than 0.0005). The free fraction of 1,25-(OH)2D remained unchanged after estrogen. It appears that estrogen treatment increases the plasma concentration of 1,25-(OH)2D. The effect might be explained by the concomitant increase in DBP and/or by estrogen stimulation of renal 1 alpha-hydroxylase.
D015650:24,25-Dihydroxyvitamin D 3; D000293:Adolescent; D001827:Body Height; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002352:Carrier Proteins / Q000097:blood; D002648:Child; D004100:Dihydroxycholecalciferols / Q000097:blood; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006801:Humans; D014807:Vitamin D / Q000097:blood*; D014809:Vitamin D-Binding Protein
D002352:Carrier Proteins; D004100:Dihydroxycholecalciferols; D014809:Vitamin D-Binding Protein; D014807:Vitamin D; D015650:24,25-Dihydroxyvitamin D 3; D004958:Estradiol; D002117:Calcitriol; D002112:Calcifediol