Selective Blockade of T-Type Ca2+ Channels is Protective Against Alcohol-Withdrawal Induced Seizure and Mortality

Alcohol Alcohol. 2018 Sep 1;53(5):526-531. doi: 10.1093/alcalc/agy042.

Abstract

Aims: We have previously demonstrated that blockade of T-type calcium channels by the non-selective antagonist, ethosuximide (ETX), is effective at reducing electrographical and behavioral correlates of alcohol-withdrawal (WD) seizure. Here, we investigated whether blockade of these calcium channels with the selective antagonist TTA-P2 also reduces alcohol-WD seizure.

Short summary: The non-specific T-type calcium channel antagonist, ETX, is protective against alcohol-WD seizure. However, the mechanism of this effect is unclear. Here, we provide evidence that further suggests selective blockade of T-type calcium channels are protective against alcohol-WD seizure and WD-related mortality.

Methods: We used an intermittent ethanol exposure model to produce WD-induced hyperexcitability in DBA/2 J mice. Seizure severity was intensified with the chemoconvulsant pentylenetetrazole (PTZ).

Results: TTA-P2 (10 mg/kg) reduced seizure severity in mice undergoing alcohol WD with concurrent PTZ treatment (20 mg/kg). Moreover, TTA-P2 (20 and 40 mg/kg) was also protective against PTZ-induced (40 mg/kg) seizure and mortality.

Conclusions: These results are consistent with prior results using ETX, and suggest that the protective effects of ETX and TTA-P2 against EtOH WD seizures are mediated by T-type calcium channels.

MeSH terms

  • Alcohol Withdrawal Seizures / chemically induced
  • Alcohol Withdrawal Seizures / mortality
  • Alcohol Withdrawal Seizures / prevention & control*
  • Animals
  • Benzamides / therapeutic use*
  • Calcium Channel Blockers / therapeutic use*
  • Calcium Channels, T-Type / physiology*
  • Dose-Response Relationship, Drug
  • Ethanol / toxicity*
  • Male
  • Mice
  • Mice, Inbred DBA
  • Pentylenetetrazole / toxicity
  • Piperidines / therapeutic use*
  • Seizures / chemically induced
  • Seizures / mortality
  • Seizures / prevention & control*

Substances

  • 3,5-dichloro-N-(1-(2,2-dimethyltetrahydropyran-4-ylmethyl)-4-fluoropiperidin-4-ylmethyl)benzamide
  • Benzamides
  • Calcium Channel Blockers
  • Calcium Channels, T-Type
  • Piperidines
  • Ethanol
  • Pentylenetetrazole