Intracellular observations on the disinhibitory action of acetylcholine in the hippocampus

摘要: Abstract Intracellular recording (with KCl microelectrodes) from CA1 and CA3 hippocampal neurons in rats under urethane anaesthesia has revealed two kinds of facilitatory actions acetylcholine (applied microiontophoretically). One was a mild depolarization (mean + 12 mV) accompanied by rise input resistance 14%). The reversal potential for this effect much more negative than the resting potential, it differed inhibitory synaptic mean 65 mV. It therefore concluded that one action tends to reduce K conductance, as neocortical neurons. second is reduction potency potentials—evoked fimbrial or entorhinal stimulation—made evident 62% average conductance increase recorded near peak potentials. Since did not depress iontophoretic applications γ-aminobutyrate, must release γ-aminobutyrate either direct on terminals inhibition interneurons. former appears likely.