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P Sarchielli

Publications and source records attributed to P Sarchielli.

At least 19 recordsLinked to original sources
PubMed2006

Clinical-biochemical correlates of migraine attacks in rizatriptan responders and non-responders.

The present study was aimed at verifying the clinical characteristics of a typical attack in 20 migraine patients, 10 responders and 10 non-responders to rizatriptan, and at investigating any differences in the levels of neuropeptides of the trigeminovascular or parasympathetic systems [calcitonin gene-related peptide (CGRP), neurokinin A (NKA) and vasoactive intestinal peptide (VIP) measured by radioimmunoassay methods in external jugular blood] between responders and non-responders. In all responders to rizatriptan, pain was unilateral, severe, and pulsating, and in five of them at least one sign suggestive of parasympathetic system activation was recorded. Five patients who were non-responders to rizatriptan referred bilateral and non-pulsating pain, even though severe in most of them. CGRP and NKA levels measured before rizatriptan administration were significantly higher in responders than in non-responders (P < 0.0001 and P < 0.002, respectively). In the five patients with autonomic signs among rizatriptan responders, detectable VIP levels were found at baseline. One hour after rizatriptan administration, a decrease in CGRP and NKA levels was evident in the external jugular venous blood of rizatriptan responders, and this corresponded to a significant pain relief and alleviation of accompanying symptoms. VIP levels were also significantly reduced at the same time in the five patients with autonomic signs. After rizatriptan administration, CGRP and NKA levels in non-responder patients showed less significant variations at all time points after rizatriptan administration compared with rizatriptan responders. The present study, although carried out on a limited number of patients, supports recent clinical evidence of increased trigeminal activation associated with a better triptan response in migraine patients accompanied by parasympathetic activation in a subgroup of patients with autonomic signs. In contrast, the poor response seems to be correlated with a lesser degree of trigeminal activation, lower variations of trigeminal neuropeptides after triptan administration, and no evidence of parasympathetic activation at baseline.

Calcitonin Gene-Related Peptide↗
PubMed2006

Glial cell line-derived neurotrophic factor and somatostatin levels in cerebrospinal fluid of patients affected by chronic migraine and fibromyalgia.

The aim of the present study was to verify cerebrospinal fluid (CSF) levels of glial cell line-derived neurotrophic factor (GDNF) and somatostatin, both measured by sensitive immunoassay, in: 16 chronic migraine (CM) patients, 15 patients with an antecedent history of migraine without aura diagnosed as having probable chronic migraine (PCM) and probable analgesic-abuse headache (PAAH), 20 patients affected by primary fibromyalgia syndrome (PFMS), and 20 control subjects. Significantly lower levels of GDNF and somatostatin were found in the CSF of both CM and PCM + PAAH patients compared with controls (GDNF =P < 0.001, P < 0.002; somatostatin = P < 0.002, P < 0.0003), without significant difference between the two groups. PFMS patients, with and without analgesic abuse, also had significantly lower levels of both somatostatin and GDNF (P < 0.0002, P < 0.001), which did not differ from those of CM and PCM + PAAH patients. A significant positive correlation emerged between CSF values of GDNF and those of somatostatin in CM (r = 0.70, P < 0.02), PCM + PAAH (r = 0.78, P < 0.004), and PFMS patients (r = 0.68, P < 0.008). Based on experimental findings, it can be postulated that reduced CSF levels of GDNF and somatostatin in both CM and PCM + PAAH patients can contribute to sustained central sensitization underlying chronic head pain. The abuse of simple or combination analgesics does not seem to influence the biochemical changes investigated, which appear to be more strictly related to the chronic pain state, as demonstrated also for fibromyalgia.

Adult↗
PubMed2006

NF-kappaB activity and iNOS expression in monocytes from internal jugular blood of migraine without aura patients during attacks.

This study investigated nuclear factor-kappa B (NF-kappaB) activity by electrophoresis mobility gel shift assay and IkappaBalpha expression by Western blot analysis in monocytes obtained from serial samples of internal jugular venous blood taken from seven migraine patients without aura during attacks. Inducible nitric oxide synthase (iNOS) expression was also assessed by reverse transcription-polymerase chain reaction. An increase in NF-kappaB activity peaked 2 h after attack onset. This was accompanied by a transient reduction in IkappaBalpha expression. Up-regulation of iNOS was evident at 4 h, maintained at 6 h and reduced at the end of the attack. These findings substantiate the hypothesis of transitory delayed inflammation, as suggested by the animal model, and suggest the possibility of using therapeutic approaches to target NF-kappaB transcription in the treatment of migraine.

Adult↗
PubMed2005

Headache characteristics in obstructive sleep apnea syndrome and insomnia.

OBJECTIVES: To determine headache characteristics in the obstructive sleep apnea syndrome (OSAS) and in insomnia. PATIENTS AND METHODS: Fifty-six OSAS patients and 50 insomnia patients were assessed in the same time period. Patients in both groups underwent an accurate interview to investigate headache occurrence and its characteristics. Results - Headache was reported by 49% of OSAS patients and 48% of insomnia patients. In OSAS patients headache had most frequently a tension-type pattern. Headache occurred on awakening in 74% of OSAS patients, more frequently than in insomnia patients (40%) (chi(2); P < 0.04). The occurrence of morning headache appears to be significantly correlated with nocturnal oxygen desaturation and OSAS severity. CONCLUSION: Headache is a common finding in both OSAS and insomnia patients. Because morning headache seems to be more specific for OSAS than insomnia, and in OSAS its occurrence seems to be associated with disease severity, we hypothesize the involvement of certain pathogenic mechanisms associated with OSAS.

Adult↗
PubMed2005

Balance disorders in headache patients: evaluation by computerized static stabilometry.

OBJECTIVES: The aim of the study was to investigate the occurrence of equilibrium disturbances in headache patients, during the interictal period, by computerized static stabilometry. MATERIALS AND METHODS: Sixty-seven patients were studied: 35 with migraine without aura (MwoA), 12 with tension-type headache (TTH) in the episodic form (ETTH) + MwoA, and 20 with only TTH [10 ETTH + 10 chronic (CTTH)]. The stabilometric parameters considered were: statokinesigram length (L) and surface (S) in open (EO) and closed (EC) eyes conditions with/without occlusal bite, EC with head retroflexion (ECR), and optokinetic stimulation (OKN). RESULTS: The alteration of at least one of the stabilometric parameters was observed in 45 patients (67.2%): 21 MwoA, 8 ETTH + MwoA, and 16 TTH (8 ETTH + 8 CTTH). CONCLUSION: In TTH patients (ETTH, CTTH, ETTH + MwoA), the stabilometric findings show a proprioceptive alteration induced by cervicofacial muscle contraction, which was peripheral in origin. In MwoA patients the alterations appear under OKN and support a control impairment in involuntary oculomotility of central origin.

Adult↗
PubMed2004

Optimized parameters for microencapsulation of pancreatic islet cells: an in vitro study clueing on islet graft immunoprotection in type 1 diabetes mellitus.

Alginate (AG)-based microcapsules may provide a selective permeable and biocompatible physical barrier to prevent islet graft (TX)-directed immune destruction. However, extent of the achieved immunoprotection will continue to be variable and unpredictable until the role of the individual mechanisms involved with TX-related inflammatory cell and immune reactivity are clarified. Macrophages (M) are believed to play a pivotal role in controlling the host/TX interaction and its consequences. We then have studied the effects of isolated rat M and their secretory products on allogeneic islets enveloped in variably sized and configured microcapsules, within in vitro mixed islet-M cocultures. In particular, we aimed to determine the sequence of immune or not immune specific cascade of early events that derive from such on interaction. One of the specific aims was to assess whether the membrane's physical intactness and conversely its even minimal rupture, along with the microcapsules' size (i.e., large vs. small) would significantly impact M reactivity and, thereby, the encapsulated islet viability and function. Special care was taken to evaluate extent of the elicited reactivity by meticulously monitoring cytokine, N2 derivative, and other proinflammatory protein curve profiles during the early M activation process. The study has preliminarily shown that, for equally formulated microcapsules, the capsular size and membrane's morphologic thoroughness are key to prevent M reactivity and possibly avoid the intracapsular islet cell damage. While elucidation of pathways involved with the encapsulated islet TX-directed host's responsiveness actually is in progress, it has clearly emerged that microcapsules should comply with well-defined physical properties and formulation specifications in order to obviate the primum movens of the inflammatory reaction process.

Alginates↗
PubMed2004

Different cytokine levels in thrombolysis patients as predictors for clinical outcome.

Thrombolytic therapy not always improves clinical outcome in ischemic stroke patients. This could cause lymphomonocyte accumulation in the infarcted brain area. These produce an excessive amount of proinflammatory cytokines, such as IL-1 beta, IL-6 and TNF-alfa. The aim of our study was to determine ILs levels in fibrinolytic therapy treated patients, compared with healthy controls and to evaluate if the varying levels can predictors of neurological outcome. Eighteen patients underwent thrombolytic treatment with t-PA within 3 h. Plasma levels of IL-1 beta, IL-6, TNF-alfa and IL-10 were determined by ELISA method before and within 24 h after t-PA infusion and compared with controls. Significantly higher levels of IL-1 beta and Il-6 emerged in stroke patients before treatment compared with the control group (P < 0.05 and 0.04, respectively). Slightly higher plasma levels of TNF-alfa and lower plasma levels of IL-10 were also found at base line in stroke patients. After thrombolytic treatment no significant variations were observed in the levels of TNF-alfa and IL-6, whereas a trend toward lower values for IL-1 beta and higher levels for IL-10 was observed. Positive correlations among the values of IL-6, TNF-alfa and National Institute of Health Stroke Scale (NIHSS) at discharges were observed. A similar correlation with modified Rankin scale score at 3 month was found. Pre-treatment cytokine status seems to influence pre-and long-term clinical outcome. Therefore an investigation into the possible predictor of cytokines seem worthy.

Aged↗
PubMed2004

Platelet-activating factor (PAF) in internal jugular venous blood of migraine without aura patients assessed during migraine attacks.

The aim of the study was to verify the production of PAF and the activity of PAF acetyl-hydrolase (PAF-AH), the enzyme involved in the catabolism of this phospholipid mediator, in migraine attacks. Their levels were determined during migraine crises in serial samples of internal jugular venous blood taken from five migraine patients without aura, who were admitted to the hospital during the crises. Internal jugular venous blood samples were taken immediately after catheter insertion at 1, 2, and 4 h after attack onset, and within 2 h from its cessation. PAF was purified by high-performance liquid chromatography (HPLC) and determined by radioimmunoassay method. The enzymatic activity of PAF-AH was measured by reverse-phase HPLC, based on the derivatization with 7-diethylaminocoumarin-3-carbonylazide. In the internal jugular venous blood of migraine patients without aura (MO), an increase was observed in PAF levels, which was already evident at the time of catheter insertion (885.6 +/- 82.8) and at the first hour (868.4 +/- 65.24) (ANOVA: P < 0.0001). PAF levels remained elevated through the second (746.8 +/- 82.95), fourth (700.6 +/- 34.93) and sixth hours (644.4 +/- 42.85), and then decreased at the end of the attack, reaching levels significantly lower than those measured at the time of catheter insertion (565.5 +/- 38.34). The activity of PAF-AH showed an opposite trend with higher values at the first hour and significantly lower values at the second and fourth hours from the beginning of the migraine attack (ANOVA: P < 0.02). The increased production of PAF may account for persistent platelet activation during migraine crises, even in the presence of an increased production of nitric oxide (NO) end-products which, on the other hand, should instead intervene in counteracting and limiting platelet activation. Potential sources of PAF production are the endothelial cells from cerebral vessels, stimulated by trigeminal neuropeptides, platelets themselves, and mast cells, as suggested by the neurogenic inflammation model.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed2003

Relevance of protein nitration in brain injury: a key pathophysiological mechanism in neurodegenerative, autoimmune, or inflammatory CNS diseases and stroke.

This review has focused on the evidence for the involvement of nitrative oxidation in certain neurodegenerative disorders (Parkinson's Disease, Alzheimer's Disease, Amyotrophic Lateral Sclerosis), stroke, and inflammatory and autoimmune disorders (with particular attention devoted to multiple sclerosis). The relationship between protein peroxidation and pathological changes observed in the above disorders has been reported. Whereas many of the findings are from studies with animal models and autoptic specimens from human patients, few data are available from cerebrospinal fluid and blood samples of the patients at different times and disease stages. The participation of nitrative oxidation to the direct and indirect injury of neurons and other cells of the brain (i.e., oligodendrocytes, for multiple sclerosis) is clear; less evident is their relevance for the development and progression of these disorders.Further studies should be aimed to establish the clinical and prognostic value of peroxidative markers for the CNS diseases considered. This is fundamental for the development of therapeutic interventions antagonizing nitric oxide-related species damage.

Animals↗
PubMed2003

Glutamate and nitric oxide pathway in chronic daily headache: evidence from cerebrospinal fluid.

A central sensitization has been advocated to explain chronic daily headache (CDH) due to sustained peripheral sensitization of allogenic structures responsible for sustained trigeminovascular system activation. Several mechanisms have been suggested to underlie central sensitization, but have been poorly investigated in CDH. They involve N-methyl-D-aspartate (NMDA) receptor activation and nitric oxide (NO) production and supersensitivity and increased and maintained production of sensory neuropeptides. The present study supports the above pathogenic mechanisms demonstrating a significant increase in glutamate and nitrite levels in the CSF of CDH patients, without a significant difference between patients without and those with analgesic overuse headache (P < 0.0001 and P < 0.002). The increase in CSF nitrites was accompanied by a significant rise in the CSF values of cyclic guanosine monophosphate (cGMP) in patients in comparison with controls (P < 0.0001). A statistically significant correlation emerged between visual analogic scale (VAS) values and glutamate, nitrites and cGMP. Although substance P (SP) and calcitonin gene-related peptide (CGRP), and to a lesser extent neurokinin A, were significantly increased in CSF compared with control subjects, their values did not correlate with glutamate, nitrites and cGMP levels in CSF in the patient group. The present study confirms the involvement of glutamate-NO-cGMP-mediated events underlying chronic head pain that could be the target of a new therapeutic approach which should be investigated.

Adult↗
PubMed2003

Characteristics of migraine in an out-patient population over 60 years of age.

One hundred and sixty-three consecutive patients (129 females and 34 males) over 60 years of age attending the Headache Centre of the University of Perugia in the period January 2000-December 2001 were included in the study. One hundred and fifty-two (93.3%) were affected by a primary headache disorder. According to the 1988 IHS Criteria, their prevailing attacks could be diagnosed as migraine without aura (MwoA) in 57.2% of cases (n = 87) and as migraine with aura (MwA) in 11.8% of cases (n = 18). Attacks both in MwoA and MwA were unilateral and of severe-to-moderate intensity in 45% and 50% of cases. Head pain was referred as pulsating by 56% and 38.9% of MwoA patients MwA patients, respectively. Aggravation with routine daily activities was present in 72.4% and 61.1% in MwoA and MwA patient groups. The most frequent accompanying symptoms were photophobia and phonophobia. Headache attacks were of shorter duration in MwA patients, but in 3.4% of MwoA patients attacks lasted between 2 and 4 h. Of patients affected by MwA, 55% referred, together with the typical attacks, symptoms of aura not followed by headache. A worsening of headache in the last 5 years was reported by 67.8% and 44.4% of MwoA and MwA patients, respectively. Of the patients with MwoA, 86.2% (n = 75), and 83.3% (n = 15) of those with MwA used symptomatic drugs for their attacks. In the majority of cases they took more than one analgesic or non steroidal anti-inflammatory drug. A total of 51.7% of patients with MwoA and 55.5% of patients with MwA were under prophylactic treatment. Preventive drugs included antidepressants, beta-blockers, calcium channel antagonists and antiepileptic drugs. The choice of symptomatic or prophylactic drugs was made, in the majority of cases, on the basis of concomitant diseases.

Aged↗
PubMed2002

Localized (1)H magnetic resonance spectroscopy in mainly cortical gray matter of patients with multiple sclerosis.

The brain water fraction (R), the brain water transverse relaxation time (T2), the atrophy index (alpha) and the absolute concentration of the principal brain metabolites (NAA, Cho and Cr) were measured by localized proton magnetic resonance spectroscopy in the occipito-parietal cortex (mainly gray matter) of 15 relapsing-remitting (R-R) multiple sclerosis (MS) patients, 15 secondary progressive (SP) MS patients and 8 healthy subjects. Significantly lower values of N-acetylaspartate (NAA), creatine (Cr) and the NAA/Cr ratio in the occipito-parietal cortex were detected in SP MS patients than in R-R MS and control subjects (p < 0.01). Moreover, MS patients showed shorter T2 water relaxation times and reduced brain water fraction compared with controls. Higher atrophy indices were also detected in the mainly occipito-parietal gray matter of MS patients, particularly in those with the progressive form. These findings suggest that the pathological process in MS is not limited to either white matter lesions or normal-appearing white matter but extends into the cortical gray matter (occipito-parietal), particularly in the progressive form of the disease. This can involve changes in neural metabolism or neural shrinkage and neuron loss. The significant increase in atrophy indices could be the expression of the relatively higher cerebrospinal fluid signal from the occipito-parietal cortex, even in the absence of obvious cortical atrophy.

Adult↗
PubMed2001

Levels of nerve growth factor in cerebrospinal fluid of chronic daily headache patients.

Nerve growth factor (NGF) levels were determined in the CSF of patients with chronic daily headache (CDH) and correlated with levels of sensory neuropeptides. Patients with CDH showed higher NGF levels in the CSF compared with control subjects (p < 0.0001). Higher CSF levels of substance P (SP) (p < 0.002) and calcitonin-gene-related peptide (CGRP) (p < 0.0001) were also found. There was a significant positive correlation between NGF and both SP and CGRP values. These findings suggest that NGF is involved in the long-lasting sensitization and sustained activation of the trigeminal system in CDH.

Adult↗
PubMed2001

Expression of TNF-alpha mRNA by peripheral blood mononuclear cells of multiple sclerosis patients treated with IFN-beta 1A.

The aim of the present study was to verify the expression of tumour necrosis factor (TNF)-alpha mRNA by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) in unstimulated peripheral blood mononuclear cells (MNCs) of 15 relapsing-remitting multiple sclerosis (MS) patients who underwent treatment with IFN-beta 1a (6 millions of international units (MIU) i.m. once a week) and in 15 untreated MS patients matched for age and expanded disability status score (EDSS). At the same time the expression of TNF-alpha mRNA was assessed in 10 healthy age-matched control subjects. All MS patients were assessed at the basal time and after 6 months. At the basal time, the band of TNF-alpha mRNA was detectable in 12 out of the 15 untreated patients and in 13 out of the 15 patients who underwent IFN-beta 1a treatment. The higher TNF-alpha mRNA was evident in patients with gadolinium-enhancing lesions. At the 6-month follow-up, 13 out of the 15 untreated patients still had detectable values of TNF-alpha mRNA and no significant difference emerged when compared with basal time. On the contrary, the expression of TNF-alpha mRNA was absent at the same time in nine out of the 15 patients treated with IFN-beta 1a. A longitudinal analysis carried out monthly in eight MS patients (four untreated and four treated) revealed a transient increase in TNF-alpha mRNA expression in MNCs of all four treated patients in the first 3 months, supporting previous findings of an early immunoenhancing effect of IFN-beta 1a. This early activation is followed by an inhibitory effect of IFN-beta 1a on TNF-alpha mRNA expression in about 2/3 of treated MS patients when assessed at 6 months. Further long-term studies are needed to confirm this immunomodulatory effect of IFN-beta 1a not only on TNF-alpha but also on other cytokines of Th(1)and Th(2)types.

Adult↗
PubMed2001

Magnetic resonance imaging and 1H-magnetic resonance spectroscopy in amyotrophic lateral sclerosis.

We aimed to increase confidence in the combined use of MRI and proton MR spectroscopy (1H-MRS) in diagnosis of amyotrophic lateral sclerosis (ALS). We investigated 12 patients with ALS, seven definite and five probable, taking into account clinical measures of motor neuron function. On T2-weighted images we found high signal in the corticospinal tract in six and low signal in the primary motor cortex in seven of the 12 patients. Atrophy of the precentral gyrus was apparent in all the patients apart from one with probable ALS. Absolute quantification of cerebral metabolites using 1H-MRS demonstrated a significantly lower mean concentration of N-acetylaspartate (NAA) in the precentral gyrus of patients with probable and definite ALS (8.5 +/- 0.62) than in control subjects (10.4 +/- 0.71; P < 0.001). NAA concentration in primary motor cortex correlated with Norris scale scores (r = 0.30; P < 0.0001) but not with the ALS Functional Rating Scale score or disease duration. Significantly lower levels of NAA were detected in patients with low signal in the motor cortex than in those without (P < 0.01). Mean choline (Cho) and creatine (Cr) values did not differ between patients with ALS and controls.

Aged↗
PubMed2001

Event-related potentials in posttraumatic headache.

OBJECTIVES: To assess impairment of cognitive functions occurring in patients with posttraumatic headache as a consequence of a minor cranial trauma in the absence of organic damage involving the central nervous system. BACKGROUND: The term posttraumatic syndrome defines a stereotypic set of symptoms following traumatic brain injury that are subjective and varied. A deficit of cognitive function and impairment of the rapid processes of learning, attention, and short-term memory have frequently been identified. Moreover, headache is the most frequent symptom reported by the patients. Due to the nature of the symptoms, a great limitation in defining the posttraumatic syndrome is represented by the lack of methods and diagnostic tools that allow quantification of the subjective disturbances and evidence of the signs indicative of central nervous system involvement in this pathological condition. METHODS: Twenty-five subjects (16 women, 9 men; mean age, 28 +/- 9 years) were examined between 3 and 6 months after the traumatic event. The P300 event-related potential was recorded by an odd-ball paradigm with an acoustic modality. The patients underwent electroencephalography and brain stem auditory evoked potentials; magnetic resonance imaging was performed to exclude the presence of cerebral lesions. RESULTS: The mean latency of P300 was increased in both central electrodes (Cz and Pz) in patients with posttraumatic syndrome compared with controls (P<.001); assuming the value of mean +/- 2 SD was the cutoff point between normal and abnormal results, the P300 latency results were altered in 13 patients (52%). In the patient group, a significant correlation was demonstrated between Zung Depression Scale score and P3 and N2 wave latencies (r = 0.54, P <.004; r = 0.56, P<.003) and between Zung Anxiety Scale scores and P3 wave latencies (r = 0.46, P<.02). CONCLUSIONS: These data suggest the usefulness of the P300 event-related potential in evaluating cognitive disturbances in patients affected by posttraumatic syndrome. Alteration of cognitive potential in such patients, even in the absence of lesions detectable by neuroimaging, indicate the functional impairment of specific cerebral areas that can occur after a traumatic event.

Adolescent↗
PubMed2000

Nitric oxide metabolites, prostaglandins and trigeminal vasoactive peptides in internal jugular vein blood during spontaneous migraine attacks.

Despite evidence emerging from the experimental model of nitroglycerin-induced headache, the endogenous increase in nitric oxide (NO) production during migraine attacks is only speculative. It has been hypothesized that there is a close relationship between activation of the L-arginine/NO pathway and production of certain vasoactive and algogenic prostaglandins during spontaneous migraine attacks, but this suggestion also needs to be confirmed. In the present study the levels of nitrites, the stable metabolites of NO, were determined with high performance liquid chromatography (HPLC) in the internal jugular venous blood of five patients affected by migraine without aura examined ictally. These samples were taken within 30 min, 1, 2, and 4 h from the onset of the attack and at the end of the ictal period. At the same time, the plasma levels of calcitonin gene-related peptide (CGRP), neurokinin A (NKA), prostaglandin E2 (PGE2) and 6 keto PGF1alpha, the stable product of PGI2, were assessed with radioimmunoassay (RIA) kits in the same samples. The levels of the intracellular messengers, cGMP and cAMP, were also measured with the RIA method. Nitrite, cGMP, CGRP and NKA levels reached their highest values at the first hour, then they tended to decrease progressively and returned, after the end of attacks, to values similar or below those detected at the time of catheter insertion (ANOVA, statistical significance: P<0.001; P<<0.002; P<0.002; P<0.003, respectively). PGE2 and 6 keto PGF1alpha, as well as cAMP levels also significantly increased at the first hour but reached a peak at the 2nd hour and remained in the same range until the 4th and 6th hours. Then their values tended to decrease after the end of attacks, becoming lower than those measured immediately after catheter positioning for internal jugular venous blood drawing (ANOVA: P<0.002, P<0.004, P<0.001, respectively). Our results support early activation of the L-arginine/NO pathway which accompanies the release of vasoactive peptides from trigeminal endings and a late rise in the synthesis of prostanoids with algogenic and vasoactive properties which may intervene in maintaining the headache phase.

Adult↗