Parathyroid hormone inhibits plasma membrane Pi transport without changing endocytic activity in opossum kidney cells

M. S. Paraiso, J. A. McAteer, S. A. Kempson

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Parathyroid hormone (PTH) inhibits Na+-dependent Pi uptake in renal epithelial cells from opossum kidney (OK). This requires an intact endocytic pathway, suggesting that one action of PTH may be to promote endocytic removal of Na+/Pi cotransporters from the cell membrane. The present study tested if PTH, at a dose that inhibited membrane Pi transport, also produced an increase in endocytic activity. Pi transport was measured in isolated plasma membrane vesicles. Endocytosis was measured by allowing cells to take up horseradish peroxidase (HRP) followed by assay of triton-sensitive (latent) HRP activity in subcellular fractions isolated by density gradient centrifugation. Incubation of OK cells with 10-7 M PTH for 3 h decreased Na+/Pi cotransport by membrane vesicles to 328 ± 54 pmol/mg/min compared to 448 ± 67 pmol/mg/min (mean ± S.E., P < 0.03) in controls. Latent HRP content of endosomal fractions was dependent on the time and temperature used to load cells with HRP and on the concentration of HRP. However, incubation of OK cells with 10-7 M PTH for either 1 or 3 h produced no change in latent HRP activity. Thus the action of PTH on the Na+/Pi cotransporter in the plasma membrane of OK cells does not require a change in the rate of endocytosis.

Original languageEnglish
Pages (from-to)143-147
Number of pages5
JournalBiochimica et Biophysica Acta - Molecular Cell Research
Volume1266
Issue number2
DOIs
StatePublished - 1995

Fingerprint

Opossums
Horseradish Peroxidase
Parathyroid Hormone
Cell Membrane
Kidney
Endocytosis
Subcellular Fractions
Membranes
Density Gradient Centrifugation
Epithelial Cells
Temperature

Keywords

  • Endocytosis
  • Kidney cell
  • Membrane vesicle
  • Parathyroid hormone
  • Phosphate transport

ASJC Scopus subject areas

  • Biophysics
  • Cell Biology
  • Molecular Biology

Cite this

Parathyroid hormone inhibits plasma membrane Pi transport without changing endocytic activity in opossum kidney cells. / Paraiso, M. S.; McAteer, J. A.; Kempson, S. A.

In: Biochimica et Biophysica Acta - Molecular Cell Research, Vol. 1266, No. 2, 1995, p. 143-147.

Research output: Contribution to journalArticle

@article{fdfa8ae99318468eb24963c3505cc405,
title = "Parathyroid hormone inhibits plasma membrane Pi transport without changing endocytic activity in opossum kidney cells",
abstract = "Parathyroid hormone (PTH) inhibits Na+-dependent Pi uptake in renal epithelial cells from opossum kidney (OK). This requires an intact endocytic pathway, suggesting that one action of PTH may be to promote endocytic removal of Na+/Pi cotransporters from the cell membrane. The present study tested if PTH, at a dose that inhibited membrane Pi transport, also produced an increase in endocytic activity. Pi transport was measured in isolated plasma membrane vesicles. Endocytosis was measured by allowing cells to take up horseradish peroxidase (HRP) followed by assay of triton-sensitive (latent) HRP activity in subcellular fractions isolated by density gradient centrifugation. Incubation of OK cells with 10-7 M PTH for 3 h decreased Na+/Pi cotransport by membrane vesicles to 328 ± 54 pmol/mg/min compared to 448 ± 67 pmol/mg/min (mean ± S.E., P < 0.03) in controls. Latent HRP content of endosomal fractions was dependent on the time and temperature used to load cells with HRP and on the concentration of HRP. However, incubation of OK cells with 10-7 M PTH for either 1 or 3 h produced no change in latent HRP activity. Thus the action of PTH on the Na+/Pi cotransporter in the plasma membrane of OK cells does not require a change in the rate of endocytosis.",
keywords = "Endocytosis, Kidney cell, Membrane vesicle, Parathyroid hormone, Phosphate transport",
author = "Paraiso, {M. S.} and McAteer, {J. A.} and Kempson, {S. A.}",
year = "1995",
doi = "10.1016/0167-4889(95)00008-G",
language = "English",
volume = "1266",
pages = "143--147",
journal = "Biochimica et Biophysica Acta - Molecular Cell Research",
issn = "0167-4889",
publisher = "Elsevier",
number = "2",

}

TY - JOUR

T1 - Parathyroid hormone inhibits plasma membrane Pi transport without changing endocytic activity in opossum kidney cells

AU - Paraiso, M. S.

AU - McAteer, J. A.

AU - Kempson, S. A.

PY - 1995

Y1 - 1995

N2 - Parathyroid hormone (PTH) inhibits Na+-dependent Pi uptake in renal epithelial cells from opossum kidney (OK). This requires an intact endocytic pathway, suggesting that one action of PTH may be to promote endocytic removal of Na+/Pi cotransporters from the cell membrane. The present study tested if PTH, at a dose that inhibited membrane Pi transport, also produced an increase in endocytic activity. Pi transport was measured in isolated plasma membrane vesicles. Endocytosis was measured by allowing cells to take up horseradish peroxidase (HRP) followed by assay of triton-sensitive (latent) HRP activity in subcellular fractions isolated by density gradient centrifugation. Incubation of OK cells with 10-7 M PTH for 3 h decreased Na+/Pi cotransport by membrane vesicles to 328 ± 54 pmol/mg/min compared to 448 ± 67 pmol/mg/min (mean ± S.E., P < 0.03) in controls. Latent HRP content of endosomal fractions was dependent on the time and temperature used to load cells with HRP and on the concentration of HRP. However, incubation of OK cells with 10-7 M PTH for either 1 or 3 h produced no change in latent HRP activity. Thus the action of PTH on the Na+/Pi cotransporter in the plasma membrane of OK cells does not require a change in the rate of endocytosis.

AB - Parathyroid hormone (PTH) inhibits Na+-dependent Pi uptake in renal epithelial cells from opossum kidney (OK). This requires an intact endocytic pathway, suggesting that one action of PTH may be to promote endocytic removal of Na+/Pi cotransporters from the cell membrane. The present study tested if PTH, at a dose that inhibited membrane Pi transport, also produced an increase in endocytic activity. Pi transport was measured in isolated plasma membrane vesicles. Endocytosis was measured by allowing cells to take up horseradish peroxidase (HRP) followed by assay of triton-sensitive (latent) HRP activity in subcellular fractions isolated by density gradient centrifugation. Incubation of OK cells with 10-7 M PTH for 3 h decreased Na+/Pi cotransport by membrane vesicles to 328 ± 54 pmol/mg/min compared to 448 ± 67 pmol/mg/min (mean ± S.E., P < 0.03) in controls. Latent HRP content of endosomal fractions was dependent on the time and temperature used to load cells with HRP and on the concentration of HRP. However, incubation of OK cells with 10-7 M PTH for either 1 or 3 h produced no change in latent HRP activity. Thus the action of PTH on the Na+/Pi cotransporter in the plasma membrane of OK cells does not require a change in the rate of endocytosis.

KW - Endocytosis

KW - Kidney cell

KW - Membrane vesicle

KW - Parathyroid hormone

KW - Phosphate transport

UR - http://www.scopus.com/inward/record.url?scp=0028953761&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028953761&partnerID=8YFLogxK

U2 - 10.1016/0167-4889(95)00008-G

DO - 10.1016/0167-4889(95)00008-G

M3 - Article

C2 - 7742379

AN - SCOPUS:0028953761

VL - 1266

SP - 143

EP - 147

JO - Biochimica et Biophysica Acta - Molecular Cell Research

JF - Biochimica et Biophysica Acta - Molecular Cell Research

SN - 0167-4889

IS - 2

ER -