The Role of M1 and M2 Receptors in Slow Muscarinic Excitation of Hippocampal Neurons
Electrical stimulation of presumed septo-hippocampal fibers induced an excitability increase in hippocampal neurons lasting 1–2 min. The excitability increase was due to a membrane depolarization and a diminuition of cell discharge accomodation. Both effects were mimicked by the exogenous application of carbachol (CCh) and blocked by atropine. The depolarization faded with repeated stimulation or during the action of exogenous agonists. The depolarization, but not the diminuition of accomodation, was sensitive to pirenzepine, suggestive of a contributon of Ml and M2 receptors.
KeywordsHippocampal Neuron Membrane Depolarization Stimulus Train Repeated Stimulation Muscarinic Receptor sUbtypes
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