Muscarinic receptor activation tunes mouse stratum oriens interneurones to amplify spike reliability.
Cholinergic activation of hippocampal targets can initiate and sustain network oscillations in vivo and in vitro, yet the impact of cholinergic modulation on the oscillatory properties of interneurones remains virtually unexplored. Using whole cell current clamp recordings in acute hippocampal slices, we investigated the influence of muscarinic receptor (mAChR) activation on the oscillatory properties of CA1 stratum oriens (SO) interneurones in vitro. In response to suprathreshold oscillatory input, mAChR activation increased spike reliability and precision, and extended the bandwidth that interneurone firing phase-locked. These suprathreshold effects were largest at theta frequencies, indicating that mAChR activation tunes active conductances to enhance firing reliability and precision to theta frequency input. Muscarinic tuning of the intrinsic oscillatory properties of interneurones is a novel mechanism that may be crucial for the genesis of the theta rhythm.
Lawrence
J Josh
JJ
Laboratory on Cellular and Synaptic Neurophysiology, National Institute of Child and Human Development, National Institutes of Health, Building 35, Rm 3C907, Bethesda, MD 20892, USA. lawrenjo@mail.nih.gov
Grinspan
Zachary M
ZM
Statland
Jeffrey M
JM
McBain
Chris J
CJ
D000818:Animals; D019706:Excitatory Postsynaptic Potentials; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D007395:Interneurons / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D008568:Memory / Q000187:drug effects; D051379:Mice; D008959:Models, Neurological; D009116:Muscarine / Q000494:pharmacology*; D018721:Muscarinic Agonists / Q000494:pharmacology*; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000378:metabolism*; D013826:Theta Rhythm / Q000187:drug effects*
D018721:Muscarinic Agonists; D011976:Receptors, Muscarinic; D009116:Muscarine