Cholinergic enhancement of penicillin-induced epileptiform discharges in pyramidal neurons of the guinea pig hippocampus.
Acetylcholine (1-20 mM) was applied to guinea pig hippocampal slices bathed in normal and penicillin-containing media. Recordings in the CA 1 pyramidal cell layer in the presence of penicillin showed that acetylcholine caused a prolonged enhancement of the extracellular field potential. Intracellular recordings documented an increase in duration of cell bursting, a decrease in burst afterhyperpolarization, and a membrane depolarization lasting 1-5 min. These results suggest that the actions of acetylcholine to increase membrane excitability interact with penicillin-induced disinhibition to enhance hippocampal epileptogenesis.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D005071:Evoked Potentials / Q000187:drug effects; D006168:Guinea Pigs; D006624:Hippocampus / Q000187:drug effects / Q000503:physiopathology*; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D010406:Penicillins / Q000494:pharmacology*; D011712:Pyramidal Tracts / Q000187:drug effects / Q000503:physiopathology*; D012640:Seizures / Q000503:physiopathology*
D010406:Penicillins; D000109:Acetylcholine