Pertussis toxin sensitivity of drug-induced potentials on the rat superior cervical ganglion.
We have investigated the action of pertussis toxin on a range of receptor-mediated responses of the rat superior cervical ganglion in vitro. The ganglia were treated with pertussis toxin for 24 h at 37 degrees C using an in vitro method. Appropriate controls were also carried out. Pertussis toxin (1 microgram/ml) reduced ganglionic hyperpolarisations mediated by adenosine, alpha 2, 5-HT1A, M2 and GABAB receptors. The GABAB-mediated hyperpolarisation of this preparation, evoked by baclofen and GABA in a bicuculline-resistant manner, has not previously been reported. Pertussis toxin did not reduce ganglionic depolarisations evoked by potassium chloride and 5-HT3, GABAA and nicotinic receptors. Depolarisations to muscarine and noradrenaline, probably mediated by M1 and beta-receptors, also appeared to be resistant to pertussis toxin. The similar sensitivity of the various ganglionic hyperpolarisations to pertussis toxin indicates that they may all be mediated by similar G-proteins.
Newberry
N R
NR
Merck Sharp & Dohme Research Laboratories, Neuroscience Research Centre, Harlow, Essex, U.K.
Gilbert
M J
MJ
D000818:Animals; D004347:Drug Interactions; D005071:Evoked Potentials / Q000187:drug effects; D005727:Ganglia, Spinal / Q000187:drug effects*; D037342:Pertussis Toxin; D051381:Rats; D010566:Virulence Factors, Bordetella / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin