Stimulation of ovine placental transport of calcium and magnesium by mid-molecule fragments of human parathyroid hormone-related protein.
Perfusion in situ of the placenta of intact or previously parathyroidectomized fetal lambs has been used to assess the ability of three mid-molecule fragments of the human parathyroid hormone-related protein (PTHrP) molecule to stimulate the placental transport of calcium and magnesium. PTHrP(67-86 amide) was most effective but some activity was also shown by PTHrP(75-86 amide) and by PTHrP (75-84) in decreasing order. This placental action of PTHrP(67-86 amide) was rapid and could be observed using the placenta from an intact fetus, whereas it was necessary to use the placenta from a previously parathyroidectomized fetus to demonstrate stimulation of placental calcium transport by PTHrP(1-84). PTHrP(67-86 amide) may resemble the molecule that activates the placental calcium pump.
Care
A D
AD
Department of Animal Physiology & Nutrition, University of Leeds, Australia.
Abbas
S K
SK
Pickard
D W
DW
Barri
M
M
Drinkhill
M
M
Findlay
J B
JB
White
I R
IR
Caple
I W
IW
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000097:blood*; D005260:Female; D008274:Magnesium / Q000097:blood*; D044162:Parathyroid Hormone-Related Protein; D016105:Parathyroidectomy; D010446:Peptide Fragments / Q000494:pharmacology*; D010477:Perfusion; D010920:Placenta / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D011506:Proteins / Q000494:pharmacology*; D012756:Sheep
D044162:Parathyroid Hormone-Related Protein; D010446:Peptide Fragments; D011506:Proteins; D008274:Magnesium; D002118:Calcium