Nimodipine's interactions with other drugs: I. Ethanol

Area of Science:

• Neuropharmacology
• Toxicology

Background:

• Ethanol's effects on the central nervous system are complex.
• Voltage-sensitive calcium channels play a role in neuronal function.

Purpose of the Study:

• To investigate the interaction between ethanol and nimodipine, a voltage-sensitive calcium channel antagonist.
• To determine if nimodipine modulates ethanol-induced neurobehavioral and physiological effects in adult mice.

Main Methods:

• Adult mice received varying doses of ethanol (0.5-2.0 g/kg) alone or with nimodipine (5 mg/kg).
• Ethanol sensitivity was assessed via rotorod activity and rectal temperature changes at 20 and 60 minutes.
• Nimodipine's effects alone were also evaluated.

Main Results:

• Nimodipine alone did not affect motor coordination or rectal temperature.
• Nimodipine potentiated ethanol-induced hypothermia at the highest ethanol dose (2.0 g/kg).
• Nimodipine exaggerated ethanol-induced motor incoordination across all tested ethanol doses.

Conclusions:

• Inhibition of voltage-dependent calcium channels can exacerbate ethanol's adverse effects.
• Calcium channel blockers may interact with ethanol, potentially increasing its toxicity.
• This suggests a role for calcium channels in mediating ethanol's neurotoxic actions.