Effects of ketamine and of high pressure on the responses to gamma-aminobutyric acid of the rat superior cervical ganglion in vitro.
1 The method of Brown & Marsh (1974) for recording of surface potentials from the rat superior cervical ganglion has been adapted for use in a high pressure chamber in order to study the effects of high pressure of helium and the possible interactions with the effects of general anaesthetics. 2 Helium pressure of 130 atm did not alter the amplitude of the responses recorded from the ganglion in response to gamma-aminobutyric acid (GABA) application (9.7 and 19.4 microM) but the amplitude of responses to a nicotinic agonist were depressed. 3 Ketamine, at concentration between 18 and 180 microM, considerably potentiated the responses of the ganglion to GABA. 4 Helium pressure (130 atm) did not reverse the potentiation of GABA by ketamine. 5 The results are discussed in connection with the ability of ketamine to oppose the behavioural effects of high pressure.
D000818:Animals; D001274:Atmospheric Pressure; D005728:Ganglia, Sympathetic / Q000187:drug effects*; D006371:Helium; D066298:In Vitro Techniques; D007649:Ketamine / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D009435:Synaptic Transmission / Q000187:drug effects; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
D006371:Helium; D005680:gamma-Aminobutyric Acid; D007649:Ketamine; D011188:Potassium