P1: KWW/KKL P2: KWW/HCN QC: KWW/FLX T1: KWW GRBT050-75 Olesen- 2057G GRBT050-Olesen-v6.cls August 5, 2005 20:30 ••Chapter 75 ◗ Biochemistry of Blood and Cerebrospinal Fluid in Tension-Type Headaches Flemming W. Bach and Michel D. Ferrari The literature on biochemistry in tension-type headache tors, were reported to be reduced in patients with TTH (TTH) is characterized by the pursuit of a large variety of in headache-free periods and further lowered during ideas about pathophysiology, and it may therefore appear headache in analogy with what was seen in migraine (59). somewhat dispersed and confusing. Indeed, in many cases Schoenen et al., on the other hand, found similar magne- similar studies have been performed that yielded contra- sium concentrations in chronic TTH and control subjects dictory results, and there may be many reasons for this. (60). Lactic and pyruvic acid levels are normal in TTH (55). First, many different designations, including chronic daily headache, (chronic) muscle contraction headache, tension headache, and chronic migraine; definitions; and Peptides criteria have been used in the past to describe clinically pa- Several peptides have been studied in TTH, and the en- tients suffering from unspecified headaches. This severely dogenous opioid peptides β-endorphin and methionine- hampers straightforward comparison of the results. Only enkephalin (met-enkephalin) received much attention in recent years have most investigators used the 1988 crite- for a period. The idea was that headache was a ria (38). Second, exclusion criteria also vary markedly, the hypoendorphin-syndrome (66). It appears from Table 75-1 most important being the use of medication at the time of that the data are inconsistent with regard to this idea. Fur- biochemical investigation and the coexistence of migraine thermore, because circulating endogenous opioid peptides or depression. Third, timing of the investigation (during are not vasoactive or have access to the central nervous headache or during headache-free periods) also varies and, system, the role of circulating opioid peptides in relation most confusingly, is not always defined. to headache is obscure (4). Plasma neuropeptide Y (NPY) Our aim is to present the reader with the available data concentrations were normal in patients suffering from in a systematic fashion and relate to some of the data with episodic TTH (ETTH) and did not differ between headache a critical eye. However, because of the assorted pattern of episodes and pain-free periods (33). Endothelin-1 concen- studies and multitude of techniques used, it will not be trations in plasma were normal in ETTH and chronic TTH possible for every substance studied to reach a final con- (CTTH) (32). clusion on a pathophysiologic or diagnostic role in TTH. The subject will be handled in sections on blood chem- istry, platelets, immune cells, and cerebrospinal fluid. Data Neuroendocrine Parameters on serotonin in the blood circulation are presented in the Adrenocorticotropic hormone (ACTH) and cortisol were platelet section because of the intimate relationship be- normal in daily chronic headache (24) and CTTH (43). tween platelet stores of serotonin and free serotonin in Melatonin is synthesized in the pineal gland from sero- plasma. tonin, but possesses negligible serotoninlike activity. Noc- turnal levels are high, whereas diurnal concentrations are BLOOD CHEMISTRY low or undetectable. Nocturnal plasma melatonin levels have been found to be reduced in a group of female tension Magnesium concentrations, which, measured in serum, headache patients (16). It was not clear from the patient may reflect brain level and, thereby, level of inhibition description whether this group also included depressed of N-methyl-D-aspartate (NMDA)–type glutamate recep- patients. The pathophysiologic interpretation of these 669 P1: KWW/KKL P2: KWW/HCN QC: KWW/FLX T1: KWW GRBT050-75 Olesen- 2057G GRBT050-Olesen-v6.cls August 5, 2005 20:30 670 Tension-Type Headaches, Cluster Headaches, and Other Primary Headaches ◗ TABLE 75-1 Plasma Levels of Opioid Peptides ity of serum norepinephrine concentrations. Suggesting a reduced noradrenergic tonus in TTH (and migraine), this Peptide n Diagnosis Result Ref. study should be reproduced on larger groups of patients β-endorphin 8 DCH Reduced (9) and the status of headache at the time of sampling made β-endorphin 11 DCH Reduced (24) clear. β-endorphin 47 DCH Normal (30) Castillo et al. measured plasma concentrations of β-endorphin 41 CTTH Normal (7) epinephrine, norepinephrine, and dopamine under stan- β-endorphin 7 ETTH Reduced (10) dardized conditions in 30 patients with ETTH in headache Met-enkephalin 9 TTH Elevated (28) phase. Pain and depression were rated on separate scales. CTTH = chronic tension-type headache; DCH = daily chronic headache; Plasma concentrations of all three catecholamines were ETTH = episodic tension-type headache; TTH = tension-type headache. lower than in control persons, supporting the idea of re- duced sympathetic activity in TTH (15). There was no as- preliminary findings is not simple, but they were suggested sociation between depression scores and catecholamine to reflect global sympathetic hypofunction. concentrations. Reduced plasma norepinephrine concen- trations also were found in 15 patients with muscle con- traction headache (69). Amino Acids Urinary excretion of 5-hydroxytryptamine (5-HT), nor- adrenaline, adrenaline, and dopamine and their acidic Ferrari et al. (26) studied plasma amino acids in migraine metabolites have been studied in female, chronic daily patients and used TTH patients and healthy normal indi- headache patients (28). Preliminary data suggested that viduals as controls. Whereas the neuroexcitatory amino in these patients the 24-hour excretion of dopamine was acids glutamic and aspartic acid were clearly elevated reduced and the circadian rhythmicity of the excretion of in migraine patients, no abnormalities could be demon- the metabolites was disturbed. Thus, the normally exist- strated in TTH patients. Also, homocysteine levels were ing difference between diurnal and nocturnal excretion normal in a study examining 20 patients with episodic TTH (diurnal > nocturnal) was absent in the headache patients. (23). Chronic daily headache patients were similar to migraine patients in this respect. More studies are needed. β Monoamines Martignoni et al. (47) found that baseline -endorphin plasma levels and the β-endorphin plasma response to Shimomura et al. (62) found that plasma levels of clonidine were significantly lower in patients with com- 3-methoxy-4-hydroxyphenylglycol (MHPG), which seem bined migraine without aura and tension headache than in to reflect central noradrenergic metabolism, predict the healthy controls. This was interpreted as evidence for fail- clinical response of TTH patients to tizanide hydrochlo- ure of central noradrenergic activity. It is not clear whether ride. Those patients who showed the best clinical response similar results could be obtained in patients with pure ten- after 4 weeks of treatment had the highest pretreatment sion headache without associated migraine. MHPG plasma levels and presumably the highest central noradrenergic activity. Several methodologic reservations, Immunologic Changes however, apply to this interesting observation, most impor- tantly the way the clinical response was measured (unde- Link and colleagues (45) have investigated several im- fined criteria, open uncontrolled evaluation), how clinical munologic parameters in cerebrospinal fluid (CSF) and outcome groups were formed and related to the MHGP plasma of patients with chronic headache (of unspeci- levels (open or blinded), and lack of clinical information fied and undefined type). However, in these studies the on the patients (use of medication, diet, and depression). headache patients were used as controls for patients with Furthermore, those patients who improved most also had multiple sclerosis, and no healthy, normal controls were by far the shortest duration of the illness, suggesting that included. Accordingly, no qualitative conclusions regard- other factors were involved. Nevertheless, this approach is ing these observations can be drawn. most promising and should be confirmed in a prospective, Nagasawa et al. (51) found slightly higher serum levels placebo-controlled, double-blind design. of complement C3 and C4 in patients with muscle contrac- Dopamine β-hydroxylase catalyzes the conversion of tion headache compared with normal individuals. How- dopamine to norepinephrine, and serum levels of this en- ever, the patient group was a mean of 10 years older than zyme were found to be reduced in 10 patients with TTH the control group, and both C3 and C4 levels increased compared with control subjects (31). The same reduction with age. Accordingly, the conclusion of Nasagawa et al. was also seen in migraine patients. Gallai et al. (31) con- that inflammatory aspects are involved in muscle contrac- sider serum activity of dopamine β-hydroxylase a useful tion headache is interesting but should be confirmed in a indicator of sympathetic activity, considering the instabil- study with a matched control group. P1: KWW/KKL P2: KWW/HCN QC: KWW/FLX T1: KWW GRBT050-75 Olesen- 2057G GRBT050-Olesen-v6.cls August 5, 2005 20:30 Biochemistry of Blood and Cerebrospinal Fluid in Tension-Type Headaches 671 Diaz-Mitoma et al. (20) reported that significantly more terized on the molecular level, these data are interesting in patients with so-called new daily persistent