Vanadate-induced oscillatory inward Cl- currents in Xenopus laevis oocytes.
Extracellularly applied sodium orthovanadate (30-3000 microM) evoked oscillatory inward Cl- currents in defolliculated Xenopus laevis oocytes. The current responses were attenuated by microinjection of EGTA into the oocytes and by treatment of the oocytes with pertussis toxin (2 micrograms/ml). The vanadate responses were not affected by preceding vanadate (1 mM) responses or an angiotensin II (200 nM) response, or by pre-application of atropine (5 microM). Intracellular injection of vanadate was ineffective. These results suggest that vanadate stimulates Ca2+ mobilization in Xenopus oocytes possibly by activating surface membrane receptors, which is coupled to pertussis toxin-sensitive G-protein.
Sakuta
H
H
Department of Pharmacology, National Defense Medical College, Saitama, Japan.
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001152:Arsenicals / Q000494:pharmacology; D001285:Atropine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D018118:Chloride Channels / Q000187:drug effects / Q000378:metabolism*; D017364:Collagenases / Q000494:pharmacology; D004594:Electrophysiology; D005260:Female; D019204:GTP-Binding Proteins / Q000378:metabolism; D066298:In Vitro Techniques; D018021:Lithium Chloride / Q000494:pharmacology; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D018408:Patch-Clamp Techniques; D037342:Pertussis Toxin; D014638:Vanadates / Q000494:pharmacology*; D010566:Virulence Factors, Bordetella / Q000494:pharmacology; D014982:Xenopus laevis
D001152:Arsenicals; D018118:Chloride Channels; D010566:Virulence Factors, Bordetella; C029341:oxophenylarsine; D000804:Angiotensin II; D014638:Vanadates; D001285:Atropine; D037342:Pertussis Toxin; D017364:Collagenases; D019204:GTP-Binding Proteins; D018021:Lithium Chloride; D002118:Calcium