Switching between persistent firing and depolarization block in individual rat CA1 pyramidal neurons

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Beate Knauer - , Ruhr University Bochum, University Medical Center Mainz (Author)
  • Motoharu Yoshida - , Ruhr University Bochum, Leibniz Institute for Neurobiology, German Center for Neurodegenerative Diseases (DZNE) - Partner Site Magdeburg, Center for Behavioral Brain Sciences (CBBS) (Author)

Abstract

The hippocampal formation plays a role in mnemonic tasks and epileptic discharges in vivo. In vitro, these functions and malfunctions may relate to persistent firing (PF) and depolarization block (DB), respectively. Pyramidal neurons of the CA1 field have previously been reported to engage in either PF or DB during cholinergic stimulation. However, it is unknown whether these cells constitute disparate populations of neurons. Furthermore, it is unclear which cell-specific peculiarities may mediate their diverse response properties. However, it has not been shown whether individual CA1 pyramidal neurons can switch between PF and DB states. Here, we used whole cell patch clamp in the current clamp mode on in vitro CA1 pyramidal neurons from acutely sliced rat tissue to test various intrinsic properties which may provoke individual cells to switch between PF and DB. We found that individual cells could switch from PF to DB, in a cholinergic agonist concentration dependent manner and depending on the parameters of stimulation. We also demonstrate involvement of TRPC and potassium channels in this switching. Finally, we report that the probability for DB was more pronounced in the proximal than in the distal half of CA1. These findings offer a potential mechanism for the stronger spatial modulation in proximal, compared to distal CA1, as place field formation was shown to be affected by DB. Taken together, our results suggest that PF and DB are not mutually exclusive response properties of individual neurons. Rather, a cell's response mode depends on a variety of intrinsic properties, and modulation of these properties enables switching between PF and DB.

Details

Original languageEnglish
Pages (from-to)817-835
Number of pages19
JournalHippocampus
Volume29
Issue number9
Publication statusPublished - Sept 2019
Peer-reviewedYes
Externally publishedYes

External IDs

Scopus 85061991073

Keywords

DFG Classification of Subject Areas according to Review Boards