The effect of myo-inositol 1,4,5-trisphosphorothioate on Cl- current pattern and intracellular Ca2+ in the Xenopus laevis oocyte.
Microinjection of myo-inositol 1,4,5-trisphosphate into voltage-clamped Xenopus laevis oocytes or the stimulation of the phosphatidylinositol cycle elicits a complex Ca2(+)-dependent Cl- current pattern. Microinjection of myo-inositol 1,3,4,5-tetrakisphosphate causes an immediate release of Ca2+, but elicits a different Cl- current pattern than myo-inositol 1,4,5-trisphosphate. We have studied the effects of myo-inositol 1,4,5-trisphosphorothioate, which can not be converted to myo-inositol 1,3,4,5-tetrakisphosphate. Myo-inositol 1,4,5-trisphosphorothioate caused an immediate release of intracellular Ca2+, as measured by fura-2 imaging. Myo-inositol 1,4,5-trisphosphorothioate generated a Cl- current pattern similar to myo-inositol 1,3,4,5-tetrakisphosphate, not myo-inositol 1,4,5-trisphosphate.
Department of Zoology, University of California, Davis 95616.
J E
JE
Ferguson
B
B
Potter
R
R
Nuccitelli
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D018118:Chloride Channels; D004594:Electrophysiology / Q000379:methods; D005260:Female; D016257:Fura-2; D066298:In Vitro Techniques; D015544:Inositol 1,4,5-Trisphosphate / Q000031:analogs & derivatives; D007295:Inositol Phosphates / Q000494:pharmacology*; D007473:Ion Channels / Q000187:drug effects / Q000502:physiology*; D007700:Kinetics; D008565:Membrane Proteins / Q000502:physiology*; D008954:Models, Biological; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*; D009946:Organothiophosphorus Compounds / Q000494:pharmacology*; D014982:Xenopus laevis
D018118:Chloride Channels; D007295:Inositol Phosphates; D007473:Ion Channels; D008565:Membrane Proteins; D009946:Organothiophosphorus Compounds; C054737:inositol 1,4,5-triphosphorothioate; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium; D016257:Fura-2