Physiological involvement of presynaptic L-type voltage-dependent calcium channels in GABA release of cerebellar molecular layer interneurons

Stéphanie Rey, Gilliane Maton, Shin’Ichiro Satake, Isabel Llano, Soosung Kang, Dalton James Surmeier, Richard B. Silverman, Thibault Collin

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

Abstract: While high threshold voltage-dependent Ca2+ channels (VDCCs) of the N and P/Q families are crucial for evoked neurotransmitter release in the mammalian CNS, it remains unclear to what extent L-type Ca2+ channels (LTCCs), which have been mainly considered as acting at postsynaptic sites, participate in the control of transmitter release. Here, we investigate the possible role of LTCCs in regulating GABA release by cerebellar molecular layer interneurons (MLIs) from rats. We found that BayK8644 (BayK) markedly increases mIPSC frequency in MLIs and Purkinje cells (PCs), suggesting that LTCCs are expressed presynaptically. Furthermore, we observed (1) a potentiation of evoked IPSCs in the presence of BayK, (2) an inhibition of evoked IPSCs in the presence of the LTCC-specific inhibitor Compound 8 (Cp8), and (3) a strong reduction of mIPSC frequency by Cp8. BayK effects are reduced by dantrolene, suggesting that ryanodine receptors act in synergy with LTCCs. Finally, BayK enhances presynaptic AP-evoked Ca2+ transients and increases the frequency of spontaneous axonal Ca2+ transients observed in TTX. Taken together, our data demonstrate that LTCCs are of primary importance in regulating GABA release by MLIs. (Figure presented.).

Original languageEnglish
Pages (from-to)390-402
Number of pages13
JournalJournal of Neurochemistry
Volume155
Issue number4
DOIs
StatePublished - Nov 2020

Bibliographical note

Publisher Copyright:
© 2020 International Society for Neurochemistry

Keywords

  • calcium channels
  • calcium imaging
  • cerebellum
  • synapse

Fingerprint

Dive into the research topics of 'Physiological involvement of presynaptic L-type voltage-dependent calcium channels in GABA release of cerebellar molecular layer interneurons'. Together they form a unique fingerprint.

Cite this