Nav: Home

Migraine rats, medical facts

January 31, 2020

London, UK: Migraine mechanisms are still far from being fully understood. Escalating data from animal models are "fact-checking" the neurophysiological and behavioral correlates of the migraine experience in humans. A series of studies published in the journal Cephalalgia, the official journal of the International Headache Society, have described the underlying mechanisms and molecules related to migraine, and how they may be affected by current anti-migraine drugs or might translate into new therapies.

Evidence suggests that migraine can originate from either central or peripheral mechanisms. Central mechanisms mean that changes in structures of the central nervous system, such as the cortex, hypothalamus, thalamus, among others, are altered, modifying brain excitability, leading to headache attacks. One mechanism believed to cause migraine is cortical spreading depression (CSD). CSD is a depolarization wave of the neurons that spreads from the occipital cortex (neck region) to parietal cortex and is also related to the migraine aura. The peripheral mechanism, on the other hand, involves the activation of nociceptors (neurons that process painful stimuli) in the meninges that surround the brain and cerebral vessels. However, CSD (with central origin) can activate the trigeminovascular system, where the nociceptors of the meninges and brain vessels come from. In a series of recent studies, these animal models are shedding more light on migraine therapies and etiological mechanisms.

Onabotulinum toxin A

Onabotulinum toxin type A (Botox) has been shown to be effective in the treatment of chronic migraine. Studies carried out with lab animals simulating neurophysiological mechanisms of the disease, are beginning to reveal how these medications work against migraine.

A research group from the Beth Israel Deaconess Medical Center and Harvard Medical School, led by Dr. Rami Burstein, showed that the induction of CSD in rats, simulating a migraine attack, activates the trigeminovascular system and increases the triggering of nociceptors from the meninges. More recently, these same group of researchers showed that in female rats the application of Botox applied peripherally to the lambdoid and sagittal sutures reduced the nociceptor shots induced by CSD by 72%, indicating that the activation of nociceptors by central migraine-inducing phenomena, such as CSD, can be blocked by Botox.


The calcitonin gene-related peptide (CGRP)) is an inflammatory and vasodilator neuropeptide that is elevated in the circulation of people with migraine and induces migraine in these patients when injected intravenously.

A growing number of studies in preclinical migraine models have shown that females are more susceptible to the nociceptive effects of CGRP, possibly due to estrogen amplifying effects on CGRP receptors. A Brazilian study, led by Dr. Juliana Geremias Chichorro, from the Federal University of Paraná, showed in another animal model of migraine that the CGRP applied within the trigeminal ganglion was able to induce neurophysiological and behavioral responses in male and female rats similar to migraine in humans, such as cutaneous allodynia (when the scalp/skin becomes painful to non-painful stimuli), intolerance to light (photophobia) and anxiety behavior. Interestingly, drugs with neuroprotective actions such as minocycline and propentophylline were effective in inhibiting the effects of CGRP only in male rats. However, sumatriptan, which is currently prescribed to abort migraine attacks, was effective in inhibiting the action of CGRP in both sexes.


Lastly, but not least, a research from Dr. Lars Edvinsson's lab at the University of Lund, Sweden, found that in rats, another migraine-related emerging neuropeptide, namely, the pituitary adenylate cyclase-activating polypeptide (PACAP-38), co-localized with CGRP in areas of the brain that are related to the origin of migraine attacks. PACAP-38 and CGRP matched well in the cerebral cortex, cerebellum, thalamus, hypothalamus, the pons and spinal trigeminal nucleus, which are well-known neuroanatomic sites related to migraine.

These are a few examples of how pre-clinical studies go further into migraine mechanisms of symptoms and behaviors in humans, as well as provide insightful data on migraine therapies' mechanisms of action.

International Headache Society

Related Migraine Articles:

Acupuncture can reduce migraine headaches
Acupuncture can reduce migraine headaches compared to both sham (placebo) acupuncture and usual care, finds a new trial from China published by The BMJ today.
Migraine rats, medical facts
Migraine mechanisms are still far from being fully understood. Escalating data from animal models are 'fact-checking' the neurophysiological and behavioral correlates of the migraine experience in humans, and how they may be affected by current anti-migraine drugs or might translate into new therapies.
Connecting the dots in the migraine brain
This dMRI study pointed to the structural strengthening of connections involving subcortical regions associated with pain processing and weakening in connections involving cortical regions associated with hyperexcitability may coexist in migraine.
Predictors of chronic migraine
A review and meta-analysis found predictors of chronic migraine. Depression, high frequency attacks, medication overuse and allodynia increased the chances for new onset chronic migraine, while annual income -- US$ 50,000 showed a protective effect.
On nitroglycerin, cardiovascular homeostasis and...bam, migraine!
Researchers in Leiden, The Netherlands, found an exaggerated cardiovascular response to nitroglycerin infusion in migraine patients, suggesting an elevated systemic sensitivity to this compound in this population.
All roads lead to migraine
Dr. Samaira Younis, from the Danish Headache Center in Copenhagen, Denmark, shares her research results, which suggests there are no differences between migraine attacks clinical characteristics following administration of 2 different compounds in patients, CGRP and sildenafil, meaning they share common cellular signaling pathways.
Running away from exercise: The curious case of migraine
In spite of the widespread recommendation for regular physical activity as a strategy to manage migraine, for some patients, exercise can instead trigger migraine attacks.
Migraine prevention in children and adolescents
Two medicines already used to prevent migraine in adults also showed efficacy in adolescents with migraine.
Got a migraine? Relief may already be on your medicine shelf
According to a new report in The American Journal of Medicine, published by Elsevier, aspirin can be considered an effective and safe option to other, more expensive medications to treat acute migraines as well as prevent recurrent attacks.
Migraine headaches? Consider aspirin for treatment and prevention
Evidence from 13 randomized trials of the treatment of migraine in 4,222 patients and tens of thousands of patients in prevention of recurrent attacks supports the use of high dose aspirin from 900 to 1,300 milligrams to treat acute migraine as well as low dose daily aspirin from 81 to 325 milligrams to prevent recurrent attacks.
More Migraine News and Migraine Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#568 Poker Face Psychology
Anyone who's seen pop culture depictions of poker might think statistics and math is the only way to get ahead. But no, there's psychology too. Author Maria Konnikova took her Ph.D. in psychology to the poker table, and turned out to be good. So good, she went pro in poker, and learned all about her own biases on the way. We're talking about her new book "The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win".
Now Playing: Radiolab

First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at