Caffeine does not affect susceptibility to cortical spreading depolarization in mice

Area of Science:

• Neuroscience
• Pharmacology
• Headache Disorders

Background:

• Migraine, a prevalent primary headache disorder, is influenced by factors also affecting cortical spreading depolarization (CSD).
• CSD, a wave of neuronal and glial depolarization, is implicated in migraine aura and potentially headache.
• Caffeine's complex relationship with headache (alleviating or triggering) necessitates investigation into its effects on CSD.

Purpose of the Study:

• To determine if caffeine modulates susceptibility to cortical spreading depolarization (CSD).
• To investigate caffeine's impact on CSD-induced cortical blood flow changes.
• To examine these effects in both wild-type and a familial hemiplegic migraine mouse model.

Main Methods:

• Mice (C57BL/6J and R192Q mutation carriers) received acute or chronic caffeine injections.
• CSD susceptibility was assessed via electrical threshold and KCl-induced CSD.
• Cortical blood flow changes during CSD were measured using laser Doppler flowmetry.

Main Results:

• Neither acute nor chronic caffeine administration altered CSD susceptibility in wild-type or R192Q mice.
• Caffeine withdrawal did not affect CSD susceptibility or related cortical blood flow changes.
• CSD-induced cortical blood flow changes remained unaffected by caffeine treatments.

Conclusions:

• Caffeine's effects on headache, whether beneficial or adverse, appear independent of CSD pathophysiology.
• The findings align with the non-migrainous presentation of caffeine-related headaches.
• CSD is unlikely to be the primary mechanism through which caffeine influences headache.