Phosphate Transport Through Placenta Brush Border Membrane
During the whole gestation, and particularly the third trimester, large quantities of inorganic phosphate (PO4) move from the mother to the foetus against a concentration gradient. Since intracellular PO4 concentration is believed to be higher than in plasma, it is probable that PO4 is actively transported through the brush border membrane (BBM) facing the maternal side of placenta. Moreover in total placenta perfusion experiments, Stulc et al. (1982–1984) reported that PO4 transport is dependent on Na concentration in the perfusate, suggesting that in placenta, as in the intestine and the kidney, PO4 is co-transported with Na.
KeywordsBrush Border Membrane Phosphate Transport Brush Border Membrane Vesicle Renal Brush Border Membrane Renal Brush Border Membrane Vesicle
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- 5.Sacktor B, Cheng L: Proton gradient-dependent phosphate transport in renal brush border membrane vesicles. J. Biol. Chem. 256: 8080–8084, 1981.Google Scholar
- 7.Danisi G, Murer H, Straub RW: Effect of pH on phosphate transport into intestinal brush border membrane vesicles. Am. J. Physiol. 246: G180 - G186, 1984.Google Scholar
- 8.Brunette MG, El Mernissi G, Doucet A: Renal sodium transport in vitamin D resistant hypophosphatemic rickets. Can. J. Physiol. & Pharmacol. In press, 1985.Google Scholar