1,25-dihydroxycholecalciferol analogs cannot replace vitamin D in normocalcemic male rats.
A possible role of vitamin D in the growth and development of rats was investigated. Impaired development was observed in normocalcemic, vitamin D-deficient male and female rats, as revealed by low intestinal calcium transport, low renal vitamin D receptor levels and poor bone mineralization. Analogs of 1,25-dihydroxycholecalciferol, possessing reduced calcium-mobilizing activity in intestine and bone but retaining differentiation activity in cultured cells, were unable to support normal development of normocalcemic, vitamin D-deficient male rats. These results suggest that either the calcium-mobilizing activity alone or both the calcium-mobilizing activity and differentiating activity of vitamin D are required for normal development or that the analogs are inactive in vivo. We also demonstrated sex-related differences in intestinal calcium transport, renal vitamin D receptor regulation and bone mineralization that were independent of vitamin D status.
Uhland-Smith
A
A
Department of Biochemistry, University of Wisconsin-Madison 53706.
DeLuca
H F
HF
D000818:Animals; D000831:Animals, Newborn; D001692:Biological Transport; D001842:Bone and Bones / Q000737:chemistry; D002117:Calcitriol / Q000097:blood / Q000494:pharmacology*; D002118:Calcium / Q000097:blood / Q000494:pharmacology; D004032:Diet; D005260:Female; D006128:Growth / Q000187:drug effects*; D007421:Intestine, Small / Q000378:metabolism; D007668:Kidney / Q000737:chemistry; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D018167:Receptors, Calcitriol / Q000032:analysis; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000494:pharmacology*; D014808:Vitamin D Deficiency / Q000378:metabolism
D018167:Receptors, Calcitriol; D014807:Vitamin D; D002117:Calcitriol; D002118:Calcium