Role of interleukin-3 in the regulation of intracellular K+ homeostasis in cultured murine haemopoietic cells.
Comparative fluorimetric, flow cytofluorimetric and fluorescence ratiometric determinations of intracellular K+ concentrations in murine haemopoietic cells (FDCP-Mix clone A4) cultured in the presence and absence of the specific growth factor Interleukin-3 were carried out with the fluorescent potassium-binding benzofuran-isophthalate acetoxymethyl ester probe. Cell suspensions kept in the absence of Interleukin-3 for 5 hours exhibited lower fluorescence intensities and smaller fluorescence ratios than their growth-factor-replete counterparts, an effect found to be reversible by readdition of the growth factor. It is concluded that Interleukin-3 deprivation of these cells leads to loss of intracellular K+. It is tentatively suggested that this deprivation-induced K+ loss might be associated with an early event in apoptotic cell death.
Laskay
G
G
Department of Physics and Instrumentation, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Manchester, U.K.
Várhelyi
T
T
Dale
R E
RE
Dexter
T M
TM
D000818:Animals; D001572:Benzofurans; D002460:Cell Line; D017077:Culture Media, Conditioned; D004988:Ethers, Cyclic; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000378:metabolism*; D006706:Homeostasis; D007377:Interleukin-3 / Q000494:pharmacology*; D051379:Mice; D011188:Potassium / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
D001572:Benzofurans; D017077:Culture Media, Conditioned; D004988:Ethers, Cyclic; D005456:Fluorescent Dyes; D007377:Interleukin-3; C095549:potassium-binding benzofuran-isophthalate acetoxymethyl ester; D011188:Potassium