Inositol tetrakisphosphates as second messengers induce Ca(++)-dependent chloride currents in Xenopus laevis oocytes.
Microinjection of inositol 1,3,4,5-tetrakisphosphate or inositol 1,4,5-trisphosphate induced distinct chloride membrane currents in defolliculated Xenopus laevis oocytes. To decide whether these Cl(-)-currents were due to the injected compounds or their metabolic products, [3H]Ins(1,3,4,5)P4 or [3H]Ins(1,4,5)P3 were injected into oocytes and their metabolites were analyzed by HPLC. Our results indicate that Ins(1,3,4,5)P4 itself or its metabolite Ins(1,3,4,6)P4 is able to induce Cl(-)-membrane currents, most likely by increasing the cytosolic Ca(++)-concentration.
Guse
A H
AH
Institut für Biochemie und Lebensmittelchemie, Abt. für Biochemie, Universität, Hamburg, FRG.
Gercken
G
G
Boysen
H
H
Schwarz
J R
JR
Meyerhof
W
W
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology; D018118:Chloride Channels; D004594:Electrophysiology / Q000379:methods; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism / Q000494:pharmacology*; D007295:Inositol Phosphates / Q000378:metabolism / Q000494:pharmacology*; D007473:Ion Channels / Q000502:physiology*; D007700:Kinetics; D008564:Membrane Potentials / Q000187:drug effects; D008565:Membrane Proteins / Q000187:drug effects / Q000502:physiology*; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*; D015290:Second Messenger Systems / Q000187:drug effects; D014982:Xenopus laevis
D018118:Chloride Channels; D007295:Inositol Phosphates; D007473:Ion Channels; D008565:Membrane Proteins; C081655:inositol-1,3,4,5-tetrakisphosphate; C081653:inositol-1,3,4,6-tetrakisphosphate; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium