Migraine Causes

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Abnormal Calcium Channels. Some migraines may be due to abnormalities in the channels within cells that transport the electrical ions calcium, magnesium, sodium, and potassium. Calcium channels appear to play a particularly critical role in migraine:

• Calcium channels regulate the release of serotonin, an important neurotransmitter in the migraine process. (A neurotransmitter is a chemical messenger that allows communication between nerves in the brain.)
• Magnesium interacts with calcium channels, and magnesium deficiencies have been detected in the brains of patients with migraine.
• Calcium channels also play a major role in cortical spreading depression, the brain event that appears to be important in migraine symptoms.

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Some patients with migraines may inherit one or more factors that impair calcium channels, making them susceptible to headaches. For example, mutations in a gene that encodes calcium channels appears to be responsible for familial hemiplegic migraine.

Sensitivity in the Central Nervous System and a Common Theory of Primary Headaches

Researchers are also investigating factors that are common to both migraines and tension-type headaches. Some research suggests that both problems may result from a continuum of abnormalities in the central nervous system (the nerves in the brain and spine). Such changes trigger a progression of symptoms starting with mild sensations, developing into tension headache, and finally, progressing in some people to a migraine.

Serotonin and Other Neurotransmitter Levels. Neurotransmitters are chemical messengers in the brain. Serotonin is a neurotransmitter (chemical messenger in the brain) that is important for sleep, well-being, and other factors that affect quality of life. Abnormalities in serotonin levels have been observed in both tension-type and migraine headache sufferers. Altered levels of other neurotransmitters, importantly dopamine and stress hormones, also occur with migraine and tension-type headaches.