Migraine and depression: biological aspects

Roads Less Traveled: Sexual Dimorphism and Mast Cell Contributions to Migraine Pathology

Migraine is a common, little understood, and debilitating disease. It is much more prominent in women than in men (~2/3 are women) but the reasons for female preponderance are not clear. Migraineurs frequently experience severe comorbidities, such as allergies, depression, irritable bowel syndrome, and others; many of the comorbidities are more common in females. Current treatments for migraine are not gender specific, and rarely are migraine and its comorbidities considered and treated by the same specialist. Thus, migraine treatments represent a huge unmet medical need, which will only be addressed with greater understanding of its underlying pathophysiology. We discuss the current knowledge about sex differences in migraine and its comorbidities, and focus on the potential role of mast cells (MCs) in both. Sex-based differences in pain recognition and drug responses, fluid balance, and the blood–brain barrier are recognized but their impact on migraine is not well studied. Furthermore, MCs are well recognized for their prominent role in allergies but much less is known about their contributions to pain pathways in general and migraine specifically. MC-neuron bidirectional communication uniquely positions these cells as potential initiators and/or perpetuators of pain. MCs can secrete nociceptor sensitizing and activating agents, such as serotonin, prostaglandins, histamine, and proteolytic enzymes that can also activate the pain-mediating transient receptor potential vanilloid channels. MCs express receptors for both estrogen and progesterone that induce degranulation upon binding. Furthermore, environmental estrogens, such as Bisphenol A, activate MCs in preclinical models but their impact on pain pathways or migraine is understudied. We hope that this discussion will encourage scientists and physicians alike to bridge the knowledge gaps linking sex, MCs, and migraine to develop better, more comprehensive treatments for migraine patients.

Phospholipase C activity increases in cerebrospinal fluid from migraineurs in proportion to the number of comorbid conditions: a case-control study

Background

Migraineurs are more often afflicted by comorbid conditions than those without primary headache disorders, though the linking pathophysiological mechanism(s) is not known. We previously reported that phosphatidylcholine-specific phospholipase C (PC-PLC) activity in cerebrospinal fluid (CSF) increased during migraine compared to the same individual’s well state. Here, we examined whether PC-PLC activity from a larger group of well-state migraineurs is related to the number of their migraine comorbidities.

Methods

In a case–control study, migraineurs were diagnosed using International Headache Society criteria, and controls had no primary headache disorder or family history of migraine. Medication use, migraine frequency, and physician-diagnosed comorbidities were recorded for all participants. Lumbar CSF was collected between the hours of 1 and 5 pm, examined immediately for cells and total protein, and stored at −80°C. PC-PLC activity in thawed CSF was measured using a fluorometric enzyme assay. Multivariable logistic regression was used to evaluate age, gender, medication use, migraine frequency, personality scores, and comorbidities as potential predictors of PC-PLC activity in CSF.

Results

A total of 18 migraineurs-without-aura and 17 controls participated. In a multivariable analysis, only the number of comorbidities was related to PC-PLC activity in CSF, and only in migraineurs [parameter estimate (standard error) = 1.77, p = 0.009].

Conclusion

PC-PLC activity in CSF increases with increasing number of comorbidities in migraine-without-aura. These data support involvement of a common lipid signaling pathway in migraine and in the comorbid conditions.

Microtrial methods for translating gene-environment dynamics into preventive interventions

Genetically informed research on behavioral outcomes holds substantial promise for guiding efforts to enhance the efficacy and effectiveness of preventive interventions, but it also poses considerable challenges given the complexities of the dynamic interplay between genes and environment. This paper introduces a relatively uncommon research design, called microtrials, to provide a means of translating basic research findings into prevention trials, particularly through introducing genetic effects into prevention models. Microtrials are defined as randomized experiments testing the effects of relatively brief and focused environmental manipulations designed to suppress specific risk mechanisms or enhance specific protective mechanisms, but not to bring about full treatment or prevention effects in distal outcomes. Microtrial methods are described in detail, with discussion of their unique advantages for translating this knowledge base into prevention research. We end by raising several issues to consider when constructing genetically sensitive microtrials.

Headache attributed to psychiatric disorders

The association between psychiatric illness and headache is widely recognized. "Headache attributed to psychiatric disorder" is a new category of secondary headache introduced in the 2004 revision of the International Classification of Headache Disorders (ICHD-II) (Headache Classification Subcommittee of the International Headache Society, 2004). It represents a new, but not conclusive, step toward a better systematization of the topic "headache and psychological factors." From the early 1990s the involvement of psychological factors in headache disorders has been clearly identified as "psychiatric comorbidity." The current conceptualization of the term implies an association, more than casual, but likely not causal, between an index disease or disorder and one or more coexisting physical or psychological pathologies. Additionally, clarifying the direction, meaning, and weight of comorbidities has pathophysiological, nosological, course, and treatment implications. However, the study of comorbidity may present a series of difficulties related to the current understanding of the etiology and pathophysiology of diseases at the center of our attention. Sometimes, as happens in the subject of headache, we proceed against a background where many issues need to be clarified. In this chapter, we analyze the past and current literature, tracing the line from "migraine personality" to "psychiatric comorbidity" to "headache attributed to psychiatric disorders." Questions related to etiology, pathophysiology, and treatment options are discussed for different headache subtypes.

Psychiatric disorders and headache familial recurrence: a study on 200 children and their parents

The main aim of the study was to examine the relationship between headache and familial recurrence of psychiatric disorders in parents and their children. Headache history and symptomatology have been collected in a clinical sample of 200 patients and their families, using a semi-structured interview (ICHD-II criteria). Psychiatric comorbidity was assessed by DSM-IV criteria. Chi squares and a loglinear analysis were computed in order to evaluate the main effects and interactions between the following factors: frequency and headache subtypes (migraine/not-migraine) in children, headache (migraine/not-migraine-absent/present) in parents, headache (absent/present) in grandparents, and psychiatric comorbidity (absent/present) have been analyzed: 94 mothers (47%) and 51 fathers (25.5%) had at least one psychiatric disorder, mainly mood and anxiety disorders. Considering the significant prevalence of Psi-co in children (P < 0.0001), we compared it with the presence of familiarity to headache: a significant interaction has been found (P < 0.05) showing that migraineurs with high familial recurrence of headache had a higher percentage (74.65%) of psychiatric disorders, than no-migraineurs (52.17%). Absence of headache familial loading seems to be related to psi-co only in no-migraine headache (87.5 vs. 45.5%). The occurrence of psychiatric disorders is high in children with headache, but a very different pattern seems to characterize migraine (familial co-transmission of migraine and Psi-Co?) if compared with non-migraine headache.

Locus of control moderates the relationship between headache pain and depression

The aim of the current study was to triangulate qualitative and quantitative data in order to examine in greater detail the relationship between self-reported headache pain severity, depression and coping styles. Psychosocial scales, headache characteristic scales and in-depth interviews were administered to 71 adults with the diagnosis of primary headache. Regression analyses with the scales showed that greater self-reported headache pain severity was associated with higher levels of depression. A high internal locus of control weakened the relationship between the headache severity and depression variables. The qualitative data supported the relationship between pain severity and internal locus of control and, in addition, revealed that perceived efficacy of pharmacologic intervention might be a related factor. The results suggested that stronger coping skills might reduce depression among headache sufferers.

The relationship of 5HTT (SLC6A4) methylation and genotype on mRNA expression and liability to major depression and alcohol dependence in subjects from the Iowa Adoption Studies

Serotonin Transporter (5HTT or SLC6A4) mRNA transcription is regulated by both genetic and epigenetic mechanisms. Unfortunately, despite intense scrutiny, the exact identity and contribution of each of these regulatory mechanisms, and their relationship to behavioral illness remain unknown. This lack of knowledge is critical because alterations in SLC6A4 function are posited to be central to a wide variety of CNS disorders. In order to address this shortcoming, we quantified 5HTTLPR genotype, SLC6A4 mRNA production and CpG methylation using biomaterial from 192 lymphoblast cell lines derived from subjects who participated in the latest wave of the Iowa Adoption Studies. We then analyzed the resulting data with respect to clinical characteristics. We confirmed prior findings that the short (s) 5HTTLPR allele is associated with lower amounts of mRNA transcription, but there was no significant effect of the "Long G" allele on mRNA transcription. We also found that CpG methylation was higher (P < 0.0008) and mRNA production (P < 0.0001) was lower in females as compared to males. Those subjects with a lifetime history of Alcohol Dependence had higher levels of SLC6A4 mRNA. There was a trend for an association of increased overall methylation with lifetime history of major depression. Finally, we confirm our prior findings that the exact levels of 5HTT mRNA expression are dependent on how it is measured. We conclude that both genetic variation and epigenetic modifications contribute to the regulation of SLC6A4 function and that more in-depth studies of the molecular mechanisms controlling gene activity and the relationship of these mechanisms to behavioral illness are indicated.

The Impact of Migraine on Patients With Major Depressive Disorder

BACKGROUND

The impact of migraine and other headache types among psychiatric outpatients with major depressive disorder (MDD) has not been fully described.

OBJECTIVE

To investigate the impact of migraine on the severity, physical, and anxiety symptoms in patients with MDD and to examine the interaction between headache and depression.

METHODS

This clinic-based study enrolled consecutive psychiatric outpatients meeting DSM-IV criteria for MDD. Headache types were diagnosed based on the International Classification of Headache Disorders, 2nd edition (2004). Three psychometric instruments were used to evaluate anxiety, depression, and physical components: the Hamilton Depression Rating Scale, the Beck Depression Inventory, and the Hospital Anxiety and Depression Scale. In addition, the interactions between headache and their depressive episode were also evaluated.

RESULTS

Compared with patients without migraine, MDD patients with comorbid migraine (n = 73, 48.3%) had higher physical and anxiety scores on the three psychometric instruments. Migraine accounted for 5% to 11% of the variance of the total scores on the three psychometric scales. Approximately half (48.5%) of patients reported headache worsening during or after a depressive episode.

CONCLUSIONS

Our study found that comorbidity of migraine in patients with MDD was associated with more anxiety and physical symptoms. Headache should not be considered as only a somatic symptom of depression, but should be treated as an important comorbid disorder because it might exacerbate or interact with depression during a depressive episode.

Examination of anxiety, hostility and psychiatric disorders in patients with migraine and tension-type headache

The role of psychological factors related to headache has long been a focus of investigation. The aim of this study was to evaluate anxiety, depression, hostility and psychological symptoms in patients with migraine and tension-type headache (TTH) and to compare the results with healthy controls. Seventy-five subjects with migraine and 55 subjects with TTH (according to the criteria of the International Headache Society classification) and a control group including 73 healthy subjects were studied. The Buss-Durkee Hostility Inventory, Brief Symptom Inventory, State-trait Anxiety Inventory, Trait form were administered to the subjects. Compared with healthy controls, the patients with headache had significantly higher scores on measures of anxiety, depression and hostility and lower scores on psychological symptoms. The present results indicate the need to distinguish the unique dimensions of anxiety, depression and hostility that should be assessed in the population with headaches.

Risk factors associated with migraine or chronic daily headache in out-patients with major depressive disorder

OBJECTIVE

This study investigated independent comorbidities and factors associated with migraine and chronic daily headache (CDH) in out-patients with major depressive disorder (MDD).

METHOD

Consecutive psychiatric out-patients fulfilling the DSM-IV criteria of MDD were enrolled. Headaches were diagnosed based on the criteria proposed by the second edition of the International Classification of the Headache Disorders. Psychiatric comorbidities were checked using the Mini International Neuropsychiatric Interview. Scores of the Hamilton Depression Rating Scale (HAMD) and duration of major depressive episodes (MDE) were evaluated. Multivariate logistic regression was used to decide risk factors.

RESULTS

One hundred and fifty-one patients (34 men and 117 women) participated in the study, among which 73 (48.3%) reported a history of migraine and 32 (21.2%) reported CDH during this MDE. Higher HAMD scores, female gender, and chronic depression were independently associated with migraine or CDH.

CONCLUSION

For MDD patients with a higher depressive severity and longer duration of MDE, especially female gender, surveillance of migraine and CDH might be indicated.

Self‐Reported Headache Frequency and Features Associated With Frequent Headaches in Canadian Young Adolescents

OBJECTIVE

To explore the associated factors for frequent headache among young adolescent Canadians.

METHODS

We analyzed the self-administered questionnaire microdata files of the National Longitudinal Survey of Children and Youth (NLSCY: 1996 to 1997). Two thousand and ninety respondents representing 793,100 Canadian youth aged 12 to 13 years were asked how often they had headaches in the previous 6 months.

RESULTS

Of the 2090 adolescents, 1998 (96%) responded. Frequent headaches of "about once a week" or more often were reported by 26.6% of them aged 12 to 13 years (95% CI: 24.2, 28.6). Frequent headaches appear to be associated with a plethora of risk factors germane to the life experience of these young adolescents. All factors were significant at P <.0001 by chi-square analysis and can be loosely categorized as school-related, lifestyle-related, or involving mental health. A multivariate Classification and Regression Tree (CART) analysis models frequent headaches on a depression scale, a self-esteem scale, and ever having smoked, with 60% sensitivity, and 65% specificity.

CONCLUSIONS

The NLSCY reveals a remarkable insight into headache frequency and the life experience of Canada's young adolescents with frequent headaches.

Recurrent brief depression--past and future

Recurrent brief depressive disorder (RBD) is a well-defined and significantly prevalent affective disorder with an increased risk of suicidal behavior and significant clinical impairment in the community and general practice. RBD is characterized by depressive episodes occurring at least once a month and lasting for only a few days. The lifetime co-occurrence of both RBD and major depressive disorder (MDD), called combined depression (CD), increases substantially the risk for suicide attempts, even more than is known for "pure" MDD. Diagnostic criteria for RBD can be found in the ICD-10 and DSM-IV and are helpful in both, research and clinical routine. Furthermore, several methodological issues are covered in this paper, which make clinical diagnostic and drug response evaluation of RBD very different from MDD. However, clinical procedures rather bear a resemblance to those used in the treatment of migraine or epilepsy. Formal differences in the course of RBD and MDD create different needs concerning the design of drug treatment studies. Absence of special methodological requirements and highly selected patient samples has probably been responsible for false negative results in double-blind, placebo-controlled treatment studies. Although several authors reported successful treatment of RBD with different compounds in about 60 patients, it is still not possible to deduce a treatment algorithm for RBD to date. Obviously, future treatment studies without the limitations of previous studies are clearly required for RBD.

Psychiatric comorbidity in chronic daily headache: pathophysiology, etiology, and diagnosis

Chronic daily headache is a challenge for clinical practitioners and researchers. Etiology, pathophysiology, diagnosis, treatment, and prognosis of chronic daily headache present many questions that need answers. A chance occurrence of psychiatric disorders (mostly anxiety and mood disorders) in patients with chronic daily headache should not be excluded. This results in the need to understand the involved mechanisms, which requires us to draw new insights into the etiology, diagnosis, treatment, and prognosis of chronic daily headache. Psychiatric comorbidity seems to be cross-related to each of these dimensions, although the meanings need to be drawn. Each domain is discussed, considering the status of knowledge and stressing the future lines of research.

[Headache in children: also a problem for child and adolescent psychiatry? Pathogenesis, comorbidity, therapy]

Headache is a recurrent somatic complaint in childhood and adolescence. In recent decades headache prevalence has increased while the age of onset has decreased. In most cases headache can be categorized as migraine or tension-type headache without significant organic pathology, i.e. head trauma, structural lesion, etc. Diagnosis according to the criteria of the International Headache Society is based on subjective reports by patients and their parents. The basic tools of clinical assessment are history, physical examination and a headache diary. Laboratory tests, including electroencephalography and imaging studies should not, as a rule, be undertaken routinely. Pathophysiological models with an impact on therapeutic interventions will be discussed. Childhood headache is often treated inappropriately in daily practice despite the availability of various options (including environmental, drug, and psychological therapy). Psychological therapy (relaxation training, biofeedback, stress management, etc.) as well as medication can be applied for prophylaxis. Minimal therapeutic interventions have been shown to be equally effective in a remarkable number of patients. Chronic Headache shows relevant comorbidity with anxiety and depression and is associated with somatization and school disorders. A careful investigation and an adequate therapy of eventual psychiatric comorbidity is therefore strongly recommended.

Platelet serotonin measures in migraine

OBJECTIVE AND BACKGROUND

Serotonergic mechanisms play an important role in the pathogenesis of headache. To search for potential indicators of altered serotonin homeostasis in migraine, we have investigated three parameters of the platelet serotonin (5HT) system, platelet serotonin level (PSL), platelet serotonin uptake (PSU), and monoamine oxidase (MAO-B) activity, in a group of 55 patients with migraine and in 81 healthy controls.

METHODS

After platelet separation, PSL was determined fluorimetrically; PSU was measured by incubating aliquots of platelet-rich plasma with six concentrations of 14C-5-HT for 60 seconds at 37 degrees C, followed by vacuum filtration; platelet MAO-B activity (toward kynuramine as a substrate) was determined fluorimetrically.

RESULTS

Values of the investigated measures, in patients versus controls, amounted to (mean +/- SD) 608 +/- 166 vs. 591 +/- 184 ng/10(9) platelets for PSL, 139 +/- 25 vs. 142 +/- 25 pmol 5HT/10(8) platelets/minute for Vmax of PSU, 376 +/- 62 vs. 404 +/- 72 nM for Km of PSU, and 15.8 +/- 5.1 vs. 14.3 +/- 5.7 nmol product/10(8) platelets/60 minutes for velocity of MAO-B. Mentioned parameters did not show statistical differences between patients and controls, with exception of a small difference in Km of PSU, reaching significance (P<0.01). After subgrouping of patients according to diagnosis (migraine with aura, migraine without aura, and migraine attack) and gender, no differences retained significance.

CONCLUSIONS

Our results indicate the absence of a measurable disturbance in 5HT homeostasis in migraine, as shown by platelet 5HT parameters, and they question the suitability of the use of mentioned blood elements in this regard.

Impact of UVA exposure on psychological parameters and circulating serotonin and melatonin

BACKGROUND

People tend to feel better after exposure to ultraviolet (UV) radiation. This study was performed to investigate the impact of UVA exposure on psychological and neuroendocrine parameters.

METHODS

Fifty-three volunteers were separated into 42 individuals who had UVA exposure and 11 individuals who had no UVA exposure. The UVA-exposed volunteers had irradiation sessions six times in a three-week period. All volunteers completed two questionnaires at baseline (T1) and at the end of the study (T3). For the determination of serotonin and melatonin serum levels of all volunteers blood samples were collected at baseline (T1), after the first UVA exposure (T2), and at the end of the study after the sixth exposure (T3).

RESULTS

UVA-exposed volunteers felt significantly more balanced, less nervous, more strengthened, and more satisfied with their appearance at T3. By contrast, the controls did not show significant changes of psychological parameters. In comparison to T1 and T3, serum serotonin was significantly higher and the serum melatonin was significantly lower for the volunteers exposed to UVA at T2. Both, for exposed and non-exposed volunteers serotonin and melatonin levels did not significantly differ at T1 and T3.

CONCLUSIONS

It remains obscure, whether the exposure to UVA or other components of the treatment were responsible for the psychological benefits observed. The changes of circulating neuroendocrine mediators found after UVA exposure at T2 may be due to an UVA-induced effect via a cutaneous pathway. Nevertheless, the positive psychological effects observed in our study cannot be attributed to circulating serotonin or melatonin.

Depression scores following migraine treatment in patients attending a specialized center for headache and neurology

OBJECTIVE

To determine the changes in clinical characteristics and depression levels among patients following treatment for migraine.

BACKGROUND

Epidemiologic studies have provided consistent evidence regarding an association between migraine and depression. In Puerto Rico, however, migraine has not yet been systematically investigated.

METHODS

A chart review of 144 Puerto Rican patients who presented with migraine, diagnosed according to the International Headache Society criteria, and depression over a 2-year period was performed. The level of depression, before and after migraine treatment, was evaluated using the Zung Self-rating Depression Scale.

RESULTS

The mean age of patients was 37.0 +/- 14.4 years; 77.1% were women. More than half (52.8%) reported severe headache and 56.9% reported a monthly frequency of five attacks or more. Nearly 9% were using antidepressant therapy and 8% were under psychiatric treatment. The mean Zung index score at baseline was 50.6 +/- 10.9. Following treatment with triptans, the intensity and frequency of migraine and the Zung index score decreased significantly (P<.00001). A trend for a greater reduction in Zung index scores among patients receiving triptan medications for more than a year was demonstrated (P =.07).

CONCLUSIONS

These results indicate that migraine treatment with triptans appears to be effective in decreasing the headache frequency and intensity, and depression levels, independent of antidepressant medication use or psychiatric treatment.

Risk factors for Alzheimer's disease: a population-based, longitudinal study in Manitoba, Canada

BACKGROUND

Current knowledge of risk factors for Alzheimer's disease (AD) is limited. Data from a longitudinal, population-based study of dementia in Manitoba, Canada were used to investigate risk factors for AD.

METHODS

Cognitively intact subjects completed a risk factor questionnaire assessing sociodemographic, genetic, environmental, medical and lifestyle exposures. Five years later, 36 subjects had developed AD and 658 remained cognitively intact.

RESULTS

Older subjects or those who had fewer years of education were at greater risk of AD. After adjusting for age, education and sex, occupational exposure to fumigants/ defoliants was a significant risk factor for AD (relative risk [RR] = 4.35; 95% CI : 1.05--17.90). A history of migraines increased the risk of AD (RR = 3.49; 95% CI : 1.39--8.77); an even stronger effect was noted among women. Self-reported memory loss at baseline was associated with subsequent development of AD (RR = 5.15; 95% CI : 2.36--11.27). Vaccinations and occupational exposure to excessive noise reduced the risk of AD.

CONCLUSIONS

Some well-known risk factors for AD were confirmed in this study and potential new risk factors were identified. The association of AD with a history of migraines and occupational exposure to defoliants/fumigants is of particular interest because these are biologically plausible risk factors.

Medical management of migraine-related dizziness and vertigo

Historically, review of migraine-related vestibular symptoms has focused on the various clinical presentations that occur and the results of diagnostic studies of vestibular function. Treatment of vestibular symptoms related to migraine has been proposed similar to that used for headache control, but few examples of the effectiveness of this therapy have been published. The purpose of this study is to present the various approaches that can be used to manage vestibular symptoms related to migraine, and to evaluate the overall effectiveness of these treatment approaches. This was a retrospective review of 89 patients diagnosed with migraine-related dizziness and vertigo. The character of vestibular symptoms, pattern of cochlear symptoms, results of auditory and vestibular tests, and comorbidity factors are presented. Treatment was individualized according to symptoms and comorbidity factors, and analyzed regarding effectiveness in control of the major vestibular symptoms of episodic vertigo, positional vertigo, and nonvertiginous dizziness. Medical management included dietary changes, medication, physical therapy, lifestyle adaptations, and acupuncture. Complete or substantial control of vestibular symptoms was achieved in 68 (92%) of 74 patients complaining of episodic vertigo; in 56 (89%) of 63 patients with positional vertigo; and 56 (86%) of 65 patients with non-vertiginous dizziness. Similarly, aural fullness was completely resolved or substantially improved in 34 (85%) of 40 patients; ear pain in 10 (63%) of 16 patients; and phonophobia in 17 (89%) of 19 patients. No patient reported worsened symptoms following medical management. The conflicting concept of a central disorder (migraine) as the cause of cochlear and vestibular dysfunction that often has peripheral features is discussed.

[Substance P, somatostatin and monoaminergic transmitters in the cerebrospinal fluid of patients with chronic idiopathic trigeminal neuralgia]

The etiology of trigeminal neuralgia is unknown, but both peripheral and central causes have been suggested. To investigate the role of central neurochemical mechanisms we measured epinephrine, norepinephrine and their breakdown product, vanilly mandelic acid (VMA), in the cerebrospinal fluid (CSF) of 16 patients (53.3 +/- 8.3 years) suffering from trigeminal neuralgia. As markers for the dopaminergic system, we determined CSF levels of dopamine and its metabolite homovanillic acid (HVA). As a marker for the serotonergic system, we measured CSF levels of serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA). In addition, levels of the neuropeptides substance P and somatostatin were determined. The concentration of norepinephrine (P < 0.01), VMA (P < 0.05) and HVA (P < 0.05) were significantly decreased in patients with trigeminal neuralgia and correlated with the duration of the disease and depression scores. 5-HIAA was also significantly decreased (P < 0.05) compared to control patients. Whereas substance P was significantly elevated (P < 0.05), somatostatin was significantly decreased (P < 0.05). Various correlations between the classical neurotransmitters and the neuropeptides could be established. We hypothesize than the sum of complex neurochemical changes plays a role in the etiology of trigeminal neuralgia, which can be separated in local and more central proceedings. The increase in substance P, a major nociceptive neuromodulator, supports the concept of a local neurogenic inflammation, possibly located in the trigeminovascular system. Depending on the duration of the disease and depression, the loss of serotonergic, dopaminergic and noradrenergic innervation seems to reflect more central changes, possibly due to alterations in their antinociceptive descending pathways.

Positron emission tomography of 5-HT transporter sites in the baboon brain with [11C]McN5652

[11C]McN5652 is a new radioligand specific for 5-hydroxytryptamine (5-HT; serotonin) transporters. In this study we used [11C]McN5652 to image the 5-HT transporter sites in baboon brain by positron emission tomography (PET). Dynamic PET studies were performed in three Papio anubis baboons. The animals were injected intravenously first with 11C-labeled (+)-McN5652([11C](+)McN5652), then with pharmacologically inactive enantiomer 11C-labeled (-)-McN5652 ([11C](-)McN5652); two animals received a third study with [11C](+)McN5652 after pretreatment with the specific 5-HT uptake site inhibitor fluoxetine (5 mg/kg). Initial uptake into the brain was similar for both [11C](+)McN5652 and [11C](-)McN5652. At later times (45-120 min after injection), only [11C](+)McN5652 showed a distribution characteristic for 5-HT uptake sites. In contrast, in studies with [11C](-)McN5652 and in those with [11C](+)McN5652 after 5-HT uptake site blockade with fluoxetine, 11C radioactivity concentrations were significantly lower and the distribution pattern was relatively even. The differences between [11C](+)-and (-)McN5652 were calculated for the time interval 95-125 min postinjection and used to estimate specific binding. Specific binding correlated well (r = 0.95, p < 0.001) with the known density of 5-HT uptake sites in human brain. These results indicate that [11C](+)McN5652 is suitable for PET imaging of 5-HT uptake sites in primate brain.

Migraine patients experience poorer subjective well-being/quality of life even between attacks

The aim of the present study was to compare the general well-being of migraine patients between attacks with that of an age- and sex-matched control group. One hundred and forty-five consecutive and eligible patients at the Gothenburg Migraine Clinic were asked about their well-being and their complaints. Using three self-administered standardized questionnaires, the Minor Symptoms Evaluation Profile (MSEP), Subjective Symptoms Assessment Profile (SSAP) and the Psychological General Well-Being (PGWB) Index, evaluable responses were obtained from 138 migraine patients. Compared with control subjects, migraineurs perceived more symptoms and greater emotional distress as well as disturbed contentment, vitality and sleep. It is concluded that the general well-being of the migraine patient is impaired, even between the attacks.