Intracellular K+ suppresses the activation of apoptosis in lymphocytes.


Journal Article

Little is known about the mechanisms of suppression of apoptosis. We have addressed the novel possibility that the level of intracellular K+ regulates the apoptotic process by controlling the activity of death enzymes. We show that K+, at normal intracellular levels, inhibits both apoptotic DNA fragmentation and caspase-3(CPP32)-like protease activation, suggesting that intracellular K+ loss must occur early during apoptosis. Direct measurement of K+ by inductively coupled plasma/mass spectrometry and flow cytometry indicates a major decrease in intracellular K+ concentration in the apoptotic cell. Flow cytometric analysis revealed that caspase and nuclease activity were restricted to the subpopulation of cells with reduced K+. Disruption of the natural K+ electrochemical gradient suppressed the activity of both caspase and nuclease independent of the mode of activation of the apoptotic inducing agent, demonstrating that a decrease in intracellular K+ concentration is a necessary, early event in programmed cell death.

Full Text

Duke Authors

Cited Authors

  • Hughes, FM; Bortner, CD; Purdy, GD; Cidlowski, JA

Published Date

  • November 28, 1997

Published In

Volume / Issue

  • 272 / 48

Start / End Page

  • 30567 - 30576

PubMed ID

  • 9374553

Pubmed Central ID

  • 9374553

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.272.48.30567


  • eng

Conference Location

  • United States