Pertussis toxin blocks a late inhibitory postsynaptic potential in hippocampal CA3 neurons.
These experiments show that a synaptic response, namely the late inhibitory postsynaptic potential (IPSP) of hippocampal CA3 neurons of rats, is blocked by pertussis toxin, an inactivator of several GTP-binding proteins (G-proteins) excluding the G-protein that stimulates adenylyl cyclase. This blockage occurred without a similar effect upon either the mossy fiber-evoked EPSP or the early (GABAa-mediated) IPSP. The toxin also blocked the response to baclofen, an agonist for a putative receptor (GABAb) mediating the late IPSP, but did not affect the response to THIP, an agonist for the receptor (GABAa) mediating the early IPSP. It is proposed that a pertussis toxin-sensitive G-protein controls the conductance of the late IPSP.
Thalmann
R H
RH
Department of Cell Biology, Baylor College of Medicine, Houston 77030.
D000200:Action Potentials / Q000187:drug effects; D037361:Adenylate Cyclase Toxin; D000818:Animals; D001418:Baclofen / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D007555:Isoxazoles / Q000494:pharmacology; D009431:Neural Conduction / Q000187:drug effects; D009433:Neural Inhibition / Q000187:drug effects*; D037342:Pertussis Toxin; D051381:Rats; D011963:Receptors, GABA-A / Q000187:drug effects / Q000502:physiology; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
D037361:Adenylate Cyclase Toxin; D007555:Isoxazoles; D011963:Receptors, GABA-A; D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin; D001418:Baclofen; C015542:gaboxadol