Interaction between ethanol and diazepam in mice: chronobiological aspects.

Area of Science:

• Pharmacology
• Chronobiology
• Neuroscience

Background:

• Benzodiazepines and ethanol exhibit synergistic effects on the central nervous system (CNS).
• The physiological impact of ethanol and diazepam may be influenced by the time of administration.
• Understanding these chronobiological interactions is crucial for assessing drug safety and efficacy.

Purpose of the Study:

• To investigate the influence of diazepam on ethanol-induced sleeping and hypothermic activity in mice.
• To examine the effects of combined ethanol and diazepam administration on spontaneous locomotor activity and motor coordination.
• To determine if these effects differ between the light and dark phases of the circadian cycle.

Main Methods:

• Experiments were conducted on mice during both the light phase (10:00-12:00 h) and the dark phase (22:00-24:00 h).
• Evaluated ethanol-induced sleeping time, hypothermia, spontaneous locomotor activity, and motor coordination (rota-rod test).
• Assessed the effects of diazepam alone and in combination with ethanol.

Main Results:

• Ethanol induced longer sleeping times and increased locomotor activity in the dark phase compared to the light phase.
• Ethanol-induced hypothermia was less pronounced during the dark phase.
• Diazepam potentiated ethanol's effects on sleep and coordination in the light phase but not the dark, while its effect on locomotor activity was stronger in the dark.

Conclusions:

• The interaction between diazepam and ethanol exhibits significant chronobiological effects impacting sleep and motor coordination.
• These findings highlight the importance of considering the time of day when administering these substances.
• The differential effects underscore the complexity of CNS drug interactions within the circadian rhythm.