title: Histamine increases the bursting activity of pyramidal cells in the CA3 region of mouse hippocampus.
abstract: An excitatory action of histamine was investigated by intracellular recording in the CA3 region of hippocampal slices. Bath application of histamine or impromidine, a H2 receptor agonist, had the following effects: (1) a depolarisation in 60% and no changes in membrane potential in 40% of the CA3 pyramids; (2) single cell firing and burst activity were evoked or more than doubled when spontaneously present; (3) the bursts were prolonged and often followed by afterdischarges instead of the normal afterhyperpolarisations (AHPs); (4) synaptic stimulation evoked large bursts instead of excitatory synaptic potentials (EPSPs) and primary burst responses became prolonged. CA3 bursts may play a decisive role in memory trace formation, their facilitation and potentiation is in keeping with a positive role of the histaminergic system in attention and learning.
authors.affiliation: Department of Physiology, Heinrich-Heine-Universität, Düsseldorf, Germany.
authors.forename: Y
authors.initials: Y
authors.lastname: Yanovsky
authors.forename: H L
authors.initials: HL
authors.lastname: Haas
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002927:Cimetidine / Q000494:pharmacology; D004558:Electric Stimulation; D005260:Female; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D006632:Histamine / Q000494:pharmacology*; D017446:Impromidine / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D010477:Perfusion; D017966:Pyramidal Cells / Q000187:drug effects* / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects
chemical_list: D002927:Cimetidine; D006632:Histamine; D017446:Impromidine