Trophoblastic giant cells of the mouse placenta contain calbindin-D9k but not the vitamin D receptor.
The effects of vitamin D deficiency on the ontogeny of calcium-binding proteins (CaBPs) and the vitamin D receptor (VDR) in the placenta and yolk sac of the mouse were examined. Maternal vitamin D status did not affect the time of appearance of CaBP-D9k (9 kDa) in the yolk sac endoderm or trophoblastic giant cells (TGCs) of the placenta. VDRs were undetectable in TGCs and yolk sac endoderm, but were present in the intraplacental yolk sac. Since yolk sac endoderm and TGCs contain CaBP but not VDR, it is unlikely that CaBP synthesis and/or activity in these cells is controlled by vitamin D. The TGCs, therefore, may be involved in vitamin D-independent transplacental transfer of calcium.
Shamley
D R
DR
Department of Anatomy and Human Biology, University of the Witwatersrand, Parktown, Johannesburg, South Africa.
Veale
G
G
Pettifor
J M
JM
Buffenstein
R
R
D000818:Animals; D064026:Calbindins; D004707:Endoderm / Q000737:chemistry / Q000378:metabolism; D005260:Female; D007150:Immunohistochemistry; D051379:Mice; D008815:Mice, Inbred Strains; D011247:Pregnancy; D018167:Receptors, Calcitriol / Q000032:analysis / Q000378:metabolism*; D064030:S100 Calcium Binding Protein G / Q000032:analysis / Q000378:metabolism*; D014327:Trophoblasts / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D014808:Vitamin D Deficiency / Q000378:metabolism*; D015017:Yolk Sac / Q000737:chemistry / Q000378:metabolism
D064026:Calbindins; D018167:Receptors, Calcitriol; D064030:S100 Calcium Binding Protein G; C576506:S100G protein, human; C576507:S100g protein, mouse