Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 

 Table of Contents  
Year : 2019  |  Volume : 32  |  Issue : 1  |  Page : 74-79

Study of calcitonin gene-related peptide level in peripheral blood of episodic and chronic migraine patients

1 Department of Neurology, Faculty of Medicine, Menoufia University, Menoufia, Egypt
2 Department of Neurology, Ministry of Population and Health, Sohag City, Egypt

Date of Submission16-Jun-2017
Date of Acceptance08-Sep-2017
Date of Web Publication17-Apr-2019

Correspondence Address:
Hedra H Gaed
20 El Emam Malek Street, Sohag City, Sohag Governate
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/mmj.mmj_448_17

Rights and Permissions

The aim of this study was to determine the level of calcitonin gene-related peptide (CGRP) in peripheral blood of patients with episodic migraine (EM) and chronic migraine (CM) compared with the control group.
Migraine is a common disabling multifactorial recurrent hereditary neurovascular headache disorder. It is burden to the person, the society, and affects one's quality of life. It occurs in childhood and puberty. CGRP increased from trigeminal nerves and play an important role in the painful phase of migraine.
Patients and methods
A cross-sectional study was conducted on 40 participants suffering from CM and EM and 20 healthy participants as a control group. Venous blood was taken and plasma separated to be stored at −70°C. CGRP was determined by enzyme-linked immunosorbent assay kit. All participates were subjected to full detailed general medical, neurological, and psychiatric history and examination.
Insignificant difference was recorded among migrainous patients and the control group regarding age, sex, distribution of computed tomography/MRI, fundus examination, and electroencephalogram, whereas migraine patients differ significantly regarding the symptoms such as nausea, vomiting, phonophobia, and photophobia. Moreover, no significant difference was found between men and women in their CGRP levels.
The level of CGRP plasma was clearly higher in peripheral blood in large series of CM and a lower degree for EM women versus control group in migraine attack.

Keywords: chronic migraine, episodic migraine, ictal plasma

How to cite this article:
El Sheikh WM, Alemam AI, Alahmar IE, Gaed HH. Study of calcitonin gene-related peptide level in peripheral blood of episodic and chronic migraine patients. Menoufia Med J 2019;32:74-9

How to cite this URL:
El Sheikh WM, Alemam AI, Alahmar IE, Gaed HH. Study of calcitonin gene-related peptide level in peripheral blood of episodic and chronic migraine patients. Menoufia Med J [serial online] 2019 [cited 2019 Aug 23];32:74-9. Available from: http://www.mmj.eg.net/text.asp?2019/32/1/74/256112

  Introduction Top

Migraine is a complex condition with a wide variety of symptoms: painful headache, sensitivity to light, disturbed vision, feeling sick, vomiting, and sensitivity to sound and smell. Migraine attacks can be very frightening and may result in having to lie down for several hours [1],[2],[3].

Migraine is a neurovascular disease, caused by primary brain dysfunction which causes the trigeminovascular system activation, followed by vasoactive neuropeptides releases, in the meninges trigeminovascular afferents activation releases inflammatory neuropeptides and other molecules that promote neurogenic inflammation and peripheral sensitization of the primary nociceptive neurons [3]. Migraine is classified into 2 types based on its frequency: chronic migraine (CM) and episodic migraine (EM). Chronic migraine defined as 15 or more headache days/month for 3 months at least, with 8 or more days/month fulfilling migraine criteria, in the absence of overuse of medication [4].

Activation stimulates release of neuropeptides and other proinflammatory mediator's development of central sensitization characterized by a lower activation threshold of second-order nociceptive neurons, allodynia and hyperalgesia; release of calcitonin gene-related peptide (CGRP) from trigeminal nerves play an essential role in the painful phase of migraine which raise neurogenic inflammation and relocate nociceptive information to the central nervous system [2].

CGRP is a 37-amino acid vasoactive neuropeptide which is found in neurons through the body that is categorized in the peripheral and central nervous systems in mammals [5]. Showing a wide innervation everywhere in the body, with extensive perivascular localization, it has an essential role in sensory and in different functions [6]. Therefore, we determined the CGRP plasma levels in peripheral blood (pb) during migraine, which may be used as a biomarker of permanent trigeminovascular activation.

  Patients and Methods Top

A cross-sectional study which enrolled 60 participants, classified into three groups. Group I consisted of 20 participants suffering from chronic daily migraine headaches. Group II consisted of 20 participants suffering from EM attacks. Group III consisted of 20 women without a history of primary headaches and with no family history.

All patients were selected from the outpatient clinic of the Neurology Department, Sohag General Hospitals in the period from November 2015 to April 2016.

Ethical consideration

All participants signed a written informed consent after explaining the objective of the study to them before beginning of the study. The consent form developed was based on the standard in Quality Improvement System in the Ministry of Population and Health in Egypt and modified according to the ethics committee of the Faculty of Medicine, Menoufia University.

Inclusion criteria

Women fulfilling the diagnostic criteria according to the Headache Classification Committee of the International Headache Society for patients and control group were included. Patients in this study were not taking prophylactic therapy for 1 week at least before investigation.

All participates were subjected to full detailed general medical, neurological, and psychological history examination and full detailed psychiatric history with more stress on the following points:

  1. Clinical evaluation: all participants underwent complete general, neurological, and psychological history and examination (headache sheet at the appendix) with more stress on the following points:

    1. Age.
    2. Duration of disease.
    3. Attack frequency per month.
    4. Usual duration of untreated attack.
    5. Headache characteristics.
    6. Associated features.

  2. Laboratory tests: including estimation of CGRP plasma, electroencephalogram (EEG), and fundus examination in all cases by a doctor of ophthalmology as follows:

    1. Estimation of CGRP plasma level in patients: by enzyme-linked immunosorbent assay (ELISA) kits (Human a-CGRP ELISA kits; East Lake Hi-Tech Development Zone, Wuhan, China) from blood samples determined from the right antecubital vein, through migraine attack and the patients did not receive any prophylactic treatment in the last week.
    2. Measurement of CGRP in the plasma (estimated sample):

    3. Fasting venous blood (3 ml) was collected in a sterile EDTA vacutainer, during the attack of headache and the participants were made to take rest for at least 2 h before drawing the blood. The sample was immediately centrifuged at 2000 rpm for 3 min and the plasma was transferred to another sterile clean vial to keep at −70°C till further use.

      CGRP assay was done with the help of Human a-CGRP ELISA kits. After the test, absorbance was measured at 450 nm with the help of an ELISA reader. The resultant readings were plotted against the standard curve to find out the concentration of CGRP in each sample (ng/ml).

    4. EEG: for each patient or control group, EEG was made under: standard conditions, photic stimulation, hyperventilation for 3–5 min, flashing at rates varying from 1 to 50 Hz. EEG was made by a 21-channel computerized machine (ATES, La Vergne, Tennessee, United States)
    5. Fundus examination in all cases by a doctor of ophthalmology.


All patients underwent a standard computed tomography or MRI scan of the brain. A neuroimaging specialist reviewed all the images.

Statistical analysis

Results were analyzed and tabulated using Microsoft Excel 2016 and SPSS v. 21 (SPSS Inc., Chicago, Illinois, USA). Percentage, mean ± SD, and median were calculated. Analytical methods includes: χ2-test, Student's, independent, and paired t-test, Mann–Whitney test, and correlation coefficient test (Microsoft One Microsoft Way, Redmond, Washington, U.S). A P value of less than 0.05 was indicated statistically significant.

  Results Top

Results show that no significant difference was found among migraine patients and controls regarding age and sex. In addition, insignificant difference was found among migrainous patients and control group regarding the distribution of computed tomography/MRI and fundus examination as well as EEG [Table 1].
Table 1: Comparison between the studied groups according to demographic data, computed tomography/MRI, and fundus examination

Click here to view

Results have shown that there was a significant difference among migraine patients regarding the associated symptoms (nausea, vomiting, phonophobia, and photophobia). Nausea occurs in almost 90% of patients, whereas vomiting occurs in about one-third of patients. Many patients experience sensory hyperexcitability manifested by photophobia and phonophobia [Table 2].
Table 2: Comparison between the studied groups according to associated symptoms

Click here to view

Results indicated that the CGRP plasma level were significantly higher in patients with CM (165.0 ± 17.9 ng/l, range: 131.8–194.6) as compared with the control group (70.5 ± 8.36 ng/l, range: 51.7–83.65, P1 < 0.001 vs. EM, P2 < 0.001 vs. tension type and cluster headache, Pcontrol < 0.001 vs. control). Patients with EM (94.1 ± 17.83 ng/l, range: 69.6–121.9, P1 < 0.001 vs. CM, P3= 0.471 vs. tension type and cluster headache, Pcontrol < 0.001 vs. controls). In addition, the CGRP of CM were significantly higher in patients with aura (191.32 ± 5.09, range: 185.45–194.60) than without aura (160.30 ± 14.93, range: 131.80–186.0). Moreover, the CGRP plasma levels in EM were significantly higher in patients with aura (109.88 ± 7.54, range: 100.70–116.30) than without aura (90.16 ± 17.56, range: 69.60–121.90) [Table 3].
Table 3: Comparison between the studied groups according to calcitonin gene-related peptide and aura in each group

Click here to view

This table shows that there was no statistically significant difference between men and women in the CGRP levels [Table 4].
Table 4: Relation between sex and calcitonin gene-related peptide in each group

Click here to view

  Discussion Top

CGRP causes cranial vasodilatation and facilitates nociception. During the migraine attack, activation of trigeminal causes the release of CGRP from presynaptic nerve terminals and induces vasodilatation and neurogenic inflammation in leptomeningeal and extracranial vessels, which increase the typical pain of migraine [7]. Poyner [8] have initiated the work on CGRP, who found that the CGRP encodes 37-amino acid neuropeptide in the neuronal tissue. After that the Lund group creates antibodies toward α-CGR in addition to improved sensitive methods to find this peptide function in cranial circulation. Intracranial vessels and the trigeminal ganglion promote this potent vasodilator peptide [9].

Our study shows that Ictal plasma CGRP concentration is elevated in pb in CM patients, and to a lower degree in women with EM compared with healthy women without a history of primary headache. Plasma CGRP in CM women were significantly higher in those with aura than without aura. Besides, plasma CGRP levels in patients with EM were significantly higher in aura patients than in those without aura.

In agreement with our results, Cernuda-Morollón [7] have found that there is an the interictal increase in CGRP plasma levels in pb in a large series of CM women and to a lower degree in EM women and was correlating with the headache intensity. In the other research, Goadsby and Edvinsson [10] reported that CGRP plasma concentrations are increased in the external jugular venous blood in migraine headaches and can abort the elevation of CGRP and the headache. When CGRP given intravenously it causes headache only in migraine women and CGRP antagonists are effective for acute migraine treatment. In contrast, Ashina [11] found that the CGRP level remains increased in migraineurs outside the headache period compared with the healthy group. Fusayasu et al. [12] found that during the interictal period there is an increase of CGRP in the blood and the saliva of migraineurs.

Jansen-Olesen and Olisan [13] showed that the CGRP level in the external jugular blood and pb is significantly different on nonheadache days, but not on the headache period in patients. Previous studies have indicated that CGRP is increased in the internal and external jugular blood through the headache [11]. Interestingly, a rise in peripheral CGRP in interictal, headache-free periods has been detected in EM women recruited from specialized headache clinics [14].

Moreover, Fusayasu et al. [12] found that the interictal level of CGRP was not increased in the plasma and in the saliva of the patients' complaint with migraine. These studies may suggest that trigeminal CGRP releasing is a reliable marker for migraine in a venous blood, and the decrease in its level may predict antimigraine effect. On the other hand, Tvedskov et al. [15] have found that there is no increase in CGRPs through migraine attacks in jugular venous samples as well. In this negative study, the researcher visited patients in their workplace or at their home and the time between taking the samples and centrifugation has been considered as too prolonged, and considering the short half-life of CGRP [16].

The differences of these results were due to the differences in participant selection, timing of blood sample collection after the last headache, source of blood sample (cubital vs. jugular), and other factors which affect the CGRP levels such as obesity, intake of fatty meals, and the amount of exercise may affect the CGRP levels [17].

If samples are taken very early in the attack, CGRP may not be elevated because it reaches its peak at 1.5 h of onset from migraine and normalizes within 6 h [18].

Whether the blood taken from the antecubital vein or the jugular vein, the main issue for us is that because migraine is primarily a cephalic neurovascular disorder, it was expected that the CGRP concentration should be increased in the jugular blood than in the pb [19]. Thus, it is not easy to detect whether the CGRP concentration is different between the blood drawn from these two sources.

Moreover, jugular blood goes to the right atrium of the heart and then to the whole body; so, it was expected that the CGRP would be present in blood collected from the antecubital vein. Additionally, the antecubital vein is easy accessible and sample recruitment is convenient if we collect blood from this site instead of puncturing any of the jugular veins. Owing to the obstacles in measuring jugular vein samples, several studies have determined the CGRP levels in the pb in a series of migraine patients [17].

The main finding of this study is that ictal period of plasma CGRP was elevated in pb in a large series of CM women and to a lower degree in EM patients.

It may allow monitoring migraine patients and their response to preventive treatment. Future studies on the role of CGRP and its receptor in CNS and intracranial structures will be very interesting.

  Conclusion Top

Plasma of CGRP was clearly higher in pb in a large series of chronic migraineurs, and to a lower degree, in EM women compared with the control group in migraine attack. Elevated peripheral CGRP levels must be interpreted as a distant sign of the trigeminovascular system activation and this help in understanding migraine mechanisms and in the treatment of migraine in the future.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Ferrari MD. Migraine pathophysiology: lessons from mouse program & genetic of human. Lancet Neurol 2015; 14:65–80.  Back to cited text no. 1
Burstein R. Sensitization of the trigeminovascular pathway: perspective and implications to migraine pathophysiology. J Clin Neurol 2015; 8:89–99.  Back to cited text no. 2
Ho TW, Edfonsun L, Gudsby PJ. CGRP in migraine pathophysiology. Nat Rev Neurol 2010; 6:573–582.  Back to cited text no. 3
Pietrobon D. Migraine: disorder of brain excitatory-inhibitory balance. Trends Neurosci 2012; 35:507–520.  Back to cited text no. 4
Eftekhari S. Distribution of CGRP in the human trigeminal ganglion. Neuroscience 2010; 169:683–696.  Back to cited text no. 5
Di Guilmi MN. Familial hemiplegic migraine mutated cav2.1 calcium channels alter inhibitory and excitatory synaptic transmission in the lateral superior olive of mice. Hear Res 2015; 319:56–68.  Back to cited text no. 6
Cernuda-Morollón R. Interictally increase of CGRP in pb as a biomarker for chronic migraine. Neurology 2013; 81:1191–1196.  Back to cited text no. 7
Poyner E. Regulation of signal transduction by calcitonin gene-related peptide receptors. Trends Pharmacol Sci 2002; 31:476–483.  Back to cited text no. 8
Olesen J. CGRP triggers migraine-like attacks in patients with migraine with aura. Cephalalgia 2009; 30:1179–1186.  Back to cited text no. 9
Goadsby P, Edvinsson J. CGRP and its receptors provide new insights in to migraine pathophysiology. Nat Rev Neurol 2010; 6:573–582.  Back to cited text no. 10
Ashina M. Evidence for increased plasma levels of CGRP in migraine outside of attacks. Pain 2000; 86:133–138.  Back to cited text no. 11
Fusayasu E, Kowa T, Nahichema K. Increased plasma substance P, CGRP and high ACE activity in migraineurs during headache-free periods. Pain 2007; 128:209–214.  Back to cited text no. 12
Jansen-Olesen I, Olisan J. PACAP-38 but not VIP induces release of CGRP from trigeminal nucleus caudal is through a receptor distinct from the PAC1 receptor. Neuropeptides 2014; 48:53–64.  Back to cited text no. 13
Nahashima K. Increased plasma substance P and CGRP levels, and high ACE activity in migraineurs during headache-free periods. Pain 2007; 128:209–214.  Back to cited text no. 14
Tvedskov JF, Lepka K, Ashinea M. Increase of CGRP in jugular blood during migraine. Ann Neurol 2005; 58:561–568.  Back to cited text no. 15
Juhasz G, Zombok T, Mudus E, Olagoas S. NO-induced migraine attack: strong increase in plasma CGRP concentration and negative correlation with platelet serotonin release. Pain 2003; 106:461–470.  Back to cited text no. 16
Sarchielli P, Alberty A, Codeny M. Nitric oxide metabolites, prostaglandins and trigeminal vasoactive peptides in internal jugular vein blood during spontaneous migraine attacks. Cephalalgia 2000; 20:907–918.  Back to cited text no. 17
Nemeth J, Johasz G, Zombok T, Jakaby B. Sumatriptan causes parallel decrease in CGRP plasma concentration and migraine headache during nitroglycerin induced migraine attack. Cephalalgia 2005; 25:179–183.  Back to cited text no. 18
Lance JW, Goadsby PJ. Mechanism and management of headache. Philadelphia J 2005; 2:12–17.  Back to cited text no. 19


  [Table 1], [Table 2], [Table 3], [Table 4]


Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

  In this article
Patients and Methods
Article Tables

 Article Access Statistics
    PDF Downloaded18    
    Comments [Add]    

Recommend this journal