• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

1990 Fiscal Year Final Research Report Summary

A Role of Subcellular Factors to Control Channels in Kidney Tubules.

Research Project

Project/Area Number 01570040
Research Category

Grant-in-Aid for General Scientific Research (C)

Allocation TypeSingle-year Grants
Research Field General physiology
Research InstitutionUniv. of Tokyo

Principal Investigator

KAWAHARA Katsumasa  Univ. of Tokyo, Physiol. Sci. Ass., 医学部(医)・第二生理, 助手 (70134525)

Co-Investigator(Kenkyū-buntansha) SUZUKI Makoto  Jikei Univ. School of Med. Sci. Ass., 第二内科, 助手 (10196868)
Project Period (FY) 1989 – 1990
KeywordsPatch-clamp / Ion channel / Cell Volume Regulation / Membrane Stretch / Ca / G proteins
Research Abstract

Using the patch-clamp technique, we investigated a mechanism of activation of single-channel currents during cell volume regulation in cultured rabbit kidney proximal tubule cells. Hypotonically induced cell-swelling increased Ca-dependent K currents, and then, Cl currents. Because cell membrane potential initially hyperpolarized, and then returned to the original level with KCl in the pipette (current-clamp mode). Omitting extracellular Ca from and adding 0.1 mM EGTA to the bath solution significantly slowed a time course of cell volume regulation. At Vp=0 mV the whole-cell K currents induced by hypotonicity decreased by 90% when a pipette-filling solution contained zero Ca and 5 mM EGTA. Addition of 5 mM Ba to the bath almost completely inhibited K currents due to cell-swelling. Activation of Cl currents due to hypotonicity was partially inhibited by either 20 uM SITS in the bath or zero Ca plus 5 mMEGTA in the pipette(whole-cell clamp condition).
In conclusion, hypotonicallyinduced cell swelling stimulates Ca-activated K channels, which may play an important role in cell volume regulation. A secondary activation of Cl currents may also be essential for the regulatory volume decrease mechanism.

  • Research Products

    (6 results)

All Other

All Publications (6 results)

  • [Publications] KAWAHARA,K.: "A stretchーactivated K^+ channel in the basolcteral membrane of xenopus Kidney proximal tubule cells." Ptlugers Ard Europedn J.of Physiol.415. 624-629 (1990)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] KAWAHARA,K.: "Hyposmotic dctivation of Cdーactivated K channels in cultured rabbit Kidney proximal tubule cells" Am.J.Physiol. 260. F27-F33 (1991)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] KAWAHARA,K.: "The Frontiers of Nephrolgy" Excerptd Medidca, 254 (1990)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] KAWAHARA, K.: "A Stretch-Activated K Channel in the Basolateral Membrane of Xenopus Kidney Proximal Tubule Cells." Pfluegers Arch. 415. 624-629 (1990)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] KAWAHARA, K.: "Hyposmotic Activation of Ca-Activated K Channels in Cultured Rabbit Kidney Proximal Tubule Cells." Am. J. Physiol.260. 27-33 (1991)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] KAWAHARA, K.: "Regulatory Volume Decrease Mechanism in Cultured Rabbit Kidney Proximal Tubule Cells." The Frontiers of Nephrology Elsevier. Amsterdam. 13-20 (1990)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 1993-08-12  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi