Effects of pentylenetetrazol on GABA receptors expressed in oocytes of Xenopus laevis: extra- and intracellular sites of action.
The convulsive agent pentylenetetrazol (PTZ) antagonized gamma-aminobutyric acid (GABA)-induced membrane currents on RNA-injected Xenopus oocytes with both extra- and intracellular applications. With extracellular administration PTZ enters the cell within a few minutes and reaches concentrations in the millimolar range. The permeability of the plasma membrane makes it possible for systemically applied PTZ to elicit its effect on the GABA-induced currents via extra- as well as intracellular sites of action.
Institute fur Physiologie der Westfalischen Wilhelms-Universitat Munster, Germany.
P
P
Bloms-Funke
M
M
Madeja
U
U
Musshoff
E J
EJ
Speckmann
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D003292:Convulsants / Q000494:pharmacology*; D005260:Female; D018756:GABA Antagonists / Q000494:pharmacology*; D005731:Ganglionic Stimulants / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D008839:Microelectrodes; D008845:Microinjections; D009865:Oocytes / Q000187:drug effects* / Q000648:ultrastructure; D018408:Patch-Clamp Techniques; D010433:Pentylenetetrazole / Q000493:pharmacokinetics / Q000494:pharmacology*; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology; D012313:RNA / Q000494:pharmacology; D051381:Rats; D018079:Receptors, GABA / Q000502:physiology*; D014982:Xenopus laevis
D003292:Convulsants; D018756:GABA Antagonists; D005731:Ganglionic Stimulants; D000644:Quaternary Ammonium Compounds; D018079:Receptors, GABA; D012313:RNA; C027917:tetramethylammonium; D010433:Pentylenetetrazole