Role of the hypophysis in the regulation of vitamin D metabolism.
Hypophysectomy of animals given maintenance levels of vitamin D and adequate levels of dietary calcium and phosphorus brings about a marked reduction in plasma 1,25-dihydroxyvitamin D3 levels and a significant elevation in plasma 24,25-dihydroxyvitamin D3 levels. The hypophysectomy, as expected, results in reduced growth and lowered plasma levels of inorganic phosphorus. The injection of growth hormone markedly increases plasma levels of 1,25-dihydroxyvitamin D3 in hypophysectomized animals while bringing about a reduction in 24,25-dihydroxyvitamin D3 levels. These results support the idea that the hypophysis plays a role in the regulation of vitamin D metabolism and that growth hormone either directly or indirectly is one of the hypophyseal factors bringing about this regulation.
D015650:24,25-Dihydroxyvitamin D 3; D000818:Animals; D001835:Body Weight; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood; D004100:Dihydroxycholecalciferols / Q000097:blood; D013006:Growth Hormone / Q000494:pharmacology; D007016:Hypophysectomy; D008297:Male; D009929:Organ Size; D010758:Phosphorus / Q000097:blood; D010902:Pituitary Gland / Q000502:physiology*; D051381:Rats; D014807:Vitamin D / Q000378:metabolism*
D004100:Dihydroxycholecalciferols; D014807:Vitamin D; D010758:Phosphorus; D015650:24,25-Dihydroxyvitamin D 3; D013006:Growth Hormone; D002117:Calcitriol; D002118:Calcium