Cyclosporin increases the density of angiotensin II subtype 1 (AT1) receptors in mouse medullary thick ascending limb cells

Mai Szu Wu, Chih Wei Yang, Chiz Tzuang Chang, Marcelle Bens, Alain Vandewalle

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Background. Cyclosporin A (CsA), a potent immunosuppressive agent, can be nephrotoxic. Because clinical studies have suggested that the intrarenal renin-angiotensin system may be involved in the mechanism responsible for CsA nephrotoxicity, we have analysed the effects of CsA on angiotensin II (Ang II) receptors in medullary thick ascending limb (mTAL) cells known to be sensitive to the action of CsA. Methods. Experiments were carried out on subcultured mouse mTAL cells. The expression of mRNA of Ang II subtype 1 and 2 (AT1 and AT2) receptors was investigated using reverse transcription-polymerase chain reaction (RT-PCR). [3H]Ang II was used for radioligand and binding studies. Fluorimetric recordings using the fluorescent dye fura-2/AM were performed to determine the effect of CsA on the intracellular calcium ([Ca2+]i) content of untreated and Ang II-treated mTAL cells. Results. Subcultured mTAL cells expressed AT1 and AT2 Ang II receptor mRNAs, and binding studies revealed that the AT1 receptors were the predominant Ang II receptor subtype (∼90%) in mTAL cells. CsA (100 ng/ml, 24 h) increased (1.7-fold) the number of Ang II receptors (untreated, 315.8; +CsA, 543.6 fmol/mg protein) without altering the KD (untreated, 7.16; +CsA, 7.06nM). CsA also significantly increased the level of [Ca2+]i measured in cultured mTAL cells both in the basal state (-CSA, 72.2; +CsA, 93.4 nM/106 cells) and in the presence of Ang II (-CSA, 97.8; +CsA, 206.3 nM/106 cells). Conclusions. These findings suggest that the increase in Ang II AT1 receptors and [Ca2+]i caused by CsA may be involved in the mechanism(s) responsible for CsA nephrotoxicity.

Original languageEnglish
Pages (from-to)1458-1465
Number of pages8
JournalNephrology Dialysis Transplantation
Volume18
Issue number8
DOIs
Publication statusPublished - Aug 1 2003
Externally publishedYes

Fingerprint

Angiotensin II
Cyclosporine
Extremities
Angiotensin Receptors
Messenger RNA
Angiotensin Type 1 Receptor
Immunosuppressive Agents
Renin-Angiotensin System
Fluorescent Dyes
Reverse Transcription
Calcium
Polymerase Chain Reaction

Keywords

  • Angiotensin-converting enzyme
  • AT receptor
  • Cyclosporin
  • Thick ascending limb cells

ASJC Scopus subject areas

  • Nephrology
  • Transplantation

Cite this

Cyclosporin increases the density of angiotensin II subtype 1 (AT1) receptors in mouse medullary thick ascending limb cells. / Wu, Mai Szu; Yang, Chih Wei; Chang, Chiz Tzuang; Bens, Marcelle; Vandewalle, Alain.

In: Nephrology Dialysis Transplantation, Vol. 18, No. 8, 01.08.2003, p. 1458-1465.

Research output: Contribution to journalArticle

Wu, Mai Szu ; Yang, Chih Wei ; Chang, Chiz Tzuang ; Bens, Marcelle ; Vandewalle, Alain. / Cyclosporin increases the density of angiotensin II subtype 1 (AT1) receptors in mouse medullary thick ascending limb cells. In: Nephrology Dialysis Transplantation. 2003 ; Vol. 18, No. 8. pp. 1458-1465.
@article{e3fce671d93e41b499dbe2c63251a15a,
title = "Cyclosporin increases the density of angiotensin II subtype 1 (AT1) receptors in mouse medullary thick ascending limb cells",
abstract = "Background. Cyclosporin A (CsA), a potent immunosuppressive agent, can be nephrotoxic. Because clinical studies have suggested that the intrarenal renin-angiotensin system may be involved in the mechanism responsible for CsA nephrotoxicity, we have analysed the effects of CsA on angiotensin II (Ang II) receptors in medullary thick ascending limb (mTAL) cells known to be sensitive to the action of CsA. Methods. Experiments were carried out on subcultured mouse mTAL cells. The expression of mRNA of Ang II subtype 1 and 2 (AT1 and AT2) receptors was investigated using reverse transcription-polymerase chain reaction (RT-PCR). [3H]Ang II was used for radioligand and binding studies. Fluorimetric recordings using the fluorescent dye fura-2/AM were performed to determine the effect of CsA on the intracellular calcium ([Ca2+]i) content of untreated and Ang II-treated mTAL cells. Results. Subcultured mTAL cells expressed AT1 and AT2 Ang II receptor mRNAs, and binding studies revealed that the AT1 receptors were the predominant Ang II receptor subtype (∼90{\%}) in mTAL cells. CsA (100 ng/ml, 24 h) increased (1.7-fold) the number of Ang II receptors (untreated, 315.8; +CsA, 543.6 fmol/mg protein) without altering the KD (untreated, 7.16; +CsA, 7.06nM). CsA also significantly increased the level of [Ca2+]i measured in cultured mTAL cells both in the basal state (-CSA, 72.2; +CsA, 93.4 nM/106 cells) and in the presence of Ang II (-CSA, 97.8; +CsA, 206.3 nM/106 cells). Conclusions. These findings suggest that the increase in Ang II AT1 receptors and [Ca2+]i caused by CsA may be involved in the mechanism(s) responsible for CsA nephrotoxicity.",
keywords = "Angiotensin-converting enzyme, AT receptor, Cyclosporin, Thick ascending limb cells",
author = "Wu, {Mai Szu} and Yang, {Chih Wei} and Chang, {Chiz Tzuang} and Marcelle Bens and Alain Vandewalle",
year = "2003",
month = "8",
day = "1",
doi = "10.1093/ndt/gfg180",
language = "English",
volume = "18",
pages = "1458--1465",
journal = "Nephrology Dialysis Transplantation",
issn = "0931-0509",
publisher = "Oxford University Press",
number = "8",

}

TY - JOUR

T1 - Cyclosporin increases the density of angiotensin II subtype 1 (AT1) receptors in mouse medullary thick ascending limb cells

AU - Wu, Mai Szu

AU - Yang, Chih Wei

AU - Chang, Chiz Tzuang

AU - Bens, Marcelle

AU - Vandewalle, Alain

PY - 2003/8/1

Y1 - 2003/8/1

N2 - Background. Cyclosporin A (CsA), a potent immunosuppressive agent, can be nephrotoxic. Because clinical studies have suggested that the intrarenal renin-angiotensin system may be involved in the mechanism responsible for CsA nephrotoxicity, we have analysed the effects of CsA on angiotensin II (Ang II) receptors in medullary thick ascending limb (mTAL) cells known to be sensitive to the action of CsA. Methods. Experiments were carried out on subcultured mouse mTAL cells. The expression of mRNA of Ang II subtype 1 and 2 (AT1 and AT2) receptors was investigated using reverse transcription-polymerase chain reaction (RT-PCR). [3H]Ang II was used for radioligand and binding studies. Fluorimetric recordings using the fluorescent dye fura-2/AM were performed to determine the effect of CsA on the intracellular calcium ([Ca2+]i) content of untreated and Ang II-treated mTAL cells. Results. Subcultured mTAL cells expressed AT1 and AT2 Ang II receptor mRNAs, and binding studies revealed that the AT1 receptors were the predominant Ang II receptor subtype (∼90%) in mTAL cells. CsA (100 ng/ml, 24 h) increased (1.7-fold) the number of Ang II receptors (untreated, 315.8; +CsA, 543.6 fmol/mg protein) without altering the KD (untreated, 7.16; +CsA, 7.06nM). CsA also significantly increased the level of [Ca2+]i measured in cultured mTAL cells both in the basal state (-CSA, 72.2; +CsA, 93.4 nM/106 cells) and in the presence of Ang II (-CSA, 97.8; +CsA, 206.3 nM/106 cells). Conclusions. These findings suggest that the increase in Ang II AT1 receptors and [Ca2+]i caused by CsA may be involved in the mechanism(s) responsible for CsA nephrotoxicity.

AB - Background. Cyclosporin A (CsA), a potent immunosuppressive agent, can be nephrotoxic. Because clinical studies have suggested that the intrarenal renin-angiotensin system may be involved in the mechanism responsible for CsA nephrotoxicity, we have analysed the effects of CsA on angiotensin II (Ang II) receptors in medullary thick ascending limb (mTAL) cells known to be sensitive to the action of CsA. Methods. Experiments were carried out on subcultured mouse mTAL cells. The expression of mRNA of Ang II subtype 1 and 2 (AT1 and AT2) receptors was investigated using reverse transcription-polymerase chain reaction (RT-PCR). [3H]Ang II was used for radioligand and binding studies. Fluorimetric recordings using the fluorescent dye fura-2/AM were performed to determine the effect of CsA on the intracellular calcium ([Ca2+]i) content of untreated and Ang II-treated mTAL cells. Results. Subcultured mTAL cells expressed AT1 and AT2 Ang II receptor mRNAs, and binding studies revealed that the AT1 receptors were the predominant Ang II receptor subtype (∼90%) in mTAL cells. CsA (100 ng/ml, 24 h) increased (1.7-fold) the number of Ang II receptors (untreated, 315.8; +CsA, 543.6 fmol/mg protein) without altering the KD (untreated, 7.16; +CsA, 7.06nM). CsA also significantly increased the level of [Ca2+]i measured in cultured mTAL cells both in the basal state (-CSA, 72.2; +CsA, 93.4 nM/106 cells) and in the presence of Ang II (-CSA, 97.8; +CsA, 206.3 nM/106 cells). Conclusions. These findings suggest that the increase in Ang II AT1 receptors and [Ca2+]i caused by CsA may be involved in the mechanism(s) responsible for CsA nephrotoxicity.

KW - Angiotensin-converting enzyme

KW - AT receptor

KW - Cyclosporin

KW - Thick ascending limb cells

UR - http://www.scopus.com/inward/record.url?scp=0041663738&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0041663738&partnerID=8YFLogxK

U2 - 10.1093/ndt/gfg180

DO - 10.1093/ndt/gfg180

M3 - Article

C2 - 12897082

AN - SCOPUS:0041663738

VL - 18

SP - 1458

EP - 1465

JO - Nephrology Dialysis Transplantation

JF - Nephrology Dialysis Transplantation

SN - 0931-0509

IS - 8

ER -