Effects of pentobarbitone, ketamine and lignocaine on synaptic transmission in the rat olfactory cortex in vitro.
The effects of pentobarbitone, ketamine and lignocaine on synaptic transmission in the rat olfactory cortex were studied. All agents depressed the presynaptic spike, the excitatory postsynaptic potential (EPSP) and the population spike evoked by stimulation of the lateral olfactory tract in a concentration-dependent manner. However, each anaesthetic had different effects on the processes of excitatory synaptic transmission. Pentobarbitone depressed primarily the EPSP, ketamine primarily the excitability of the presynaptic fibres and lignocaine the excitability of the presynaptic fibres; lignocaine also reduced the release of excitatory transmitters. None of the three agents influenced the passive membrane properties or the excitability of olfactory pyramidal cells. These data indicate that these agents block synaptic transmission in the olfactory cortex by different mechanisms.
Iwasaki
M
M
Department of Second Oral Surgery, Faculty of Dentistry, Kyushu University, Japan.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D002540:Cerebral Cortex / Q000502:physiology*; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007649:Ketamine / Q000494:pharmacology*; D008012:Lidocaine / Q000494:pharmacology*; D008297:Male; D016202:N-Methylaspartate; D009833:Olfactory Pathways / Q000502:physiology; D010069:Oxadiazoles / Q000494:pharmacology; D010424:Pentobarbital / Q000494:pharmacology*; D016318:Quisqualic Acid; D051381:Rats; D011919:Rats, Inbred Strains; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects*; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D010069:Oxadiazoles; D001224:Aspartic Acid; D005680:gamma-Aminobutyric Acid; D016202:N-Methylaspartate; D007649:Ketamine; D016318:Quisqualic Acid; D008012:Lidocaine; D010424:Pentobarbital