neuropeptide-y and Headache

The role of nitric oxide (NO) in migraine has been studied in the experimental glyceryl trinitrate (GTN)-infusion headache model. We hypothesized that GTN-induced headache may activate the trigeminovascular system and be associated with increased levels of sensory neuropeptides, including calcitonin gene-related peptide (CGRP). CGRP, vasoactive intestinal peptide (VIP), neuropeptide Y (NPY) and somatostatin plasma levels were measured before and after placebo/sumatriptan injection and during GTN-induced headache. Following a double-blind randomized cross-over design, 10 healthy volunteers received subcutaneous sumatriptan 6 mg or placebo. This was succeeded by 20 min of GTN (0.12 µg kg(-1) min(-1)) infusion. At baseline no subject reported headache (using verbal rating scale from 0 to 10) and the jugular CGRP-like immunoreactivity (-LI) level was 18.6 ± 2.5 pmol/l. After a 20-min intravenous infusion of GTN 0.12 µg kg(-1) min(-1), median peak headache intensity was 4 (range 2-6) (P < 0.05), while jugular CGRP-LI levels were unchanged (19.0 ± 2.8 pmol/l; P > 0.05). There were no changes in VIP-, NPY- or somatostatin-LI. In conclusion, the NO donor GTN appears not to induce headache via immediate CGRP release.

Topics: Adult; Calcitonin Gene-Related Peptide; Cross-Over Studies; Female; Headache; Humans; Male; Neuropeptide Y; Nitric Oxide; Nitric Oxide Donors; Nitroglycerin; Reference Values; Somatostatin; Sumatriptan; Vasoactive Intestinal Peptide; Vasoconstrictor Agents

Patients with pituitary tumours often present with disabling headache but there is no clear relationship between tumour size and headache. Neuropeptide Y (NPY) has been identified in pituitary tumours and may serve as a biochemical marker of the propensity for headache. Using immunohistochemical techniques we examined 27 consecutive pituitary adenoma specimens for NPY (including one normal postmortem control anterior pituitary specimen). A separate observer divided the patients into two groups: headache and non-headache. The association between the presence of NPY and headache was tested. NPY positive immunoreactivity was seen in 13 tumour specimens (50%, 13 of 26 pituitary tumour specimens), characterized by cytoplasmic and nuclear staining patterns. There was no significant association between the presence of NPY and headache (chi(2) = 0.9, P = 0.34). We did not observe NPY in the normal anterior pituitary control specimen. NPY was present in four of five (80%) growth hormone-secreting tumours and two of two (100%) prolactinomas, compared with four of 11 (36%) non-functioning adenomas. The mechanism of many pituitary tumour-associated headaches remains undetermined. The significance of NPY positivity in pituitary tumours is unknown, although the results of this study may implicate this peptide in the control of somatotroph and lactotroph activity. Our data do not support a clear role for NPY pituitary tumour-associated headache.

Topics: Chi-Square Distribution; Female; Gene Expression; Headache; Humans; Immunohistochemistry; Male; Middle Aged; Neuropeptide Y; Pituitary Neoplasms

Neuropeptide Y (NPY) is widely distributed throughout sympathetic nerve endings where it is co-stored and co-secreted with noradrenaline. It is considered a marker of noradrenergic function. To determine the role of NPY in the pathogenesis of juvenile headache, we determined its plasma levels in two groups of young migraine patients (with and without aura), in a group of episodic tension-type headache patients and in a group of age and sex-matched healthy subjects. Significantly lower plasma levels of NPY were evident in the migraine patients with aura (P < 0.001) and, to a lesser extent, in the migraine patients without aura (P < 0.02), both assessed in the interictal period, with respect to the control group. Plasma NPY levels tended to significantly increase during attacks in migraine patients with aura (P < 0.0009). A less evident, though significant increase was also present during attacks in migraine patients without aura (P < 0.02). No significant variations were observed between headache-free periods and attacks in tension-type headache patients. Reduced NPY levels in the interictal period can be considered further evidence of the derangement of the sympathetic function in the course of migraine, particularly that with aura. The increase in NPY levels during migraine attacks could be an expression of sympathetic activation, even though the functional status of this system is less efficient.

Topics: Adolescent; Child; Female; Headache; Humans; Male; Migraine Disorders; Muscle Contraction; Neuropeptide Y; Sensation Disorders

It has been suggested that a number of peptides may be involved in the transmission of pain. In order to evaluate the possible role of peptides in the development of headache, we have, in the present study, examined the presence of nerve fibres containing neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), substance P (SP) and calcitonin gene-related peptide (CGRP) in human temporal and occipital tissues. In the skin, delicate VIP, SP and CGRP fibres occur beneath the epidermis, sometimes running into the folds of the dermal ridges. In deeper layers of the dermis, small blood vessels are occasionally surrounded by single nerve fibres containing NPY, VIP, SP and CGRP. Large temporal and occipital arteries are surrounded by a meshwork of such fibres. In addition, NPY and VIP fibres are seen around sweat glands and hair follicles. Smooth muscle bundles in the dermis are surrounded by VIP fibres, whereas the temporal muscle per se is devoid of such fibres.

Topics: Calcitonin Gene-Related Peptide; Fluorescent Antibody Technique; Headache; Histocytochemistry; Humans; Muscles; Nerve Fibers; Neuropeptide Y; Neuropeptides; Skin; Substance P; Sweat Glands; Temporal Arteries; Temporal Muscle; Vasoactive Intestinal Peptide