Cyclothiazide induces robust epileptiform activity in rat hippocampal neurons both in vitro and in vivo

Jinshun Qi, Yun Wang, Min Jiang, Philippa Warren, Gong Chen

Research output: Contribution to journalArticlepeer-review

34 Scopus citations

Abstract

Cyclothiazide (CTZ) is a potent blocker of AMPA receptor desensitization. We have recently demonstrated that CTZ also inhibits GABAA receptors.Here we report that CTZ induces robust epileptiform activity in hippocampal neurons both in vitro and in vivo. We first found that chronic treatment of hippocampal cultures with CTZ (5 μM, 48 h) resuts in epileptiform activity in the majority of neurons (80%). The epileptiform activity lasts more than 48 h after washing off CTZ, suggesting a permanent change of the neural network properties after CTZ treatment. We then demonstrated in in vivo recordings that injection of CTZ (5 μmol in 5 μl) into the lateral ventricles of anaesthetized rats also induces spontaneous epileptiform activity in the hippocampal CA1 region. The epileptogenic effect of CTZ is probably due to its enhancing glutamatergic neurotransmission as shown by increasing the frequency and decay time of mEPSCs, and simultaneously inhibiting GABAergic neurotransmission by reducing the frequency of mIPSCs. Comparing to a well-known epileptogenic agent kainic acid (KA), CTZ affects neuronal activity mainly through modulating synaptic transmission without significant change of the intrinsic membrane excitability. Unlike KA, which induces significant cell death in hippocampal cultures, CTZ treatment does not result in any apparent neuronal death. Therefore, the CTZ-induced epilepsy model may provide a novel research tool to elucidate the molecular and cellular mechanisms of epileptogenesis without any complication from drug-induced cell death. The long-lasting epileptiform activity after CTZ washout may also make it a very useful model in screening antiepileptic drugs.

Original languageEnglish (US)
Pages (from-to)605-618
Number of pages14
JournalJournal of Physiology
Volume571
Issue number3
DOIs
StatePublished - Mar 2006

All Science Journal Classification (ASJC) codes

  • Physiology

Fingerprint Dive into the research topics of 'Cyclothiazide induces robust epileptiform activity in rat hippocampal neurons both in vitro and in vivo'. Together they form a unique fingerprint.

Cite this