The actions of halothane on spontaneous activity, action potential shape and synaptic connections of the giant serotonin-containing neurone of Lymnaea stagnalis (L.).
1. Cerebral giant cells (CGCs) in the isolated central nervous system (CNS) of the pond snail Lymnaea stagnalis (L.) exhibit bursting activity when superfused with anaesthetic concentrations of halothane. 2. Calcium-dependent components of the CGC action potential appear more sensitive to halothane than do other ionic mechanisms. 3. Higher concentrations of halothane block the chemical synaptic connection between CGC and buccal motoneurone B1, but have no effect on the strong electrotonic coupling between the CGCs. 4. The mechanisms underlying CGC bursting and synaptic block in the presence of halothane are discussed.
Girdlestone
D
D
Department of Physiology, University of Leeds, U.K.
McCrohan
C R
CR
Winlow
W
W
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000502:physiology; D002490:Central Nervous System / Q000187:drug effects; D006221:Halothane / Q000494:pharmacology*; D066298:In Vitro Techniques; D007395:Interneurons / Q000187:drug effects; D008195:Lymnaea; D009046:Motor Neurons / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D012701:Serotonin / Q000502:physiology; D013569:Synapses / Q000187:drug effects
D012701:Serotonin; D002118:Calcium; D006221:Halothane