Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The headache phase of migraine may develop as the result of an abnormal interaction (and perhaps an abnormal release) of vasoactive neurotransmitters from terminals of the trigeminal nerve with large intracranial and extracranial blood-vessels. These blood-vessels, which dilate during the headache phase of migraine, are thought to receive axonal projections from all three divisions of the trigeminal nerve. Substance P, a potent vasodilating peptide, seems to be released from trigeminal nerve endings in response to nervous stimulation and is involved in the transmission of painful stimuli within the periphery. The vasoactive molecule serotonin, implicated in the pathogenesis of migraine, coexists with substance P in some terminals of the central nervous system and is present within the trigeminal ganglia. Within this nerve serotonin may modulate the function of primary sensory neurons. The abnormal release of substance P or as yet unidentified peptides or other transmitters from the fifth cranial nerve may explain both the hemicranial pain and the vasodilation which are characteristic of the headache of migraine.
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PMID:Neurotransmitters and the fifth cranial nerve: is there a relation to the headache phase of migraine? 9 Sep 71

Intravenous administration of an alpha-adrenoceptor agonist, UK-14,304, a histamine H3 receptor agonist, R(-)-alpha-methyl-histamine (alpha-MeHA) or SMS 201-995 (a synthetic octapeptide analogue of somatostatin), blocked plasma protein (125I-albumin) extravasation within rat and/or guinea pig dura mater following unilateral electrical trigeminal ganglion stimulation or capsaicin administration. The extravasation caused by the administration of the neuropeptide mediator, substance P, was not inhibited by any of the three compounds. Blockade by UK-14,304 was completely antagonized by pretreatment with the highly selective alpha 2-antagonist, idazoxan, as was alpha-MeHA by pretreatment with the highly selective histamine H3 antagonist, thioperamide. Taken together, the results are consistent with blockade by prejunctional alpha 2, histamine H3 and probably somatostatin receptors which may be coupled to inhibition of neuropeptide release. Because 5-HT1-like agonists, which are useful for treating migraine and related headaches, share similar inhibitory properties in this in vivo model, the significance of prejunctional alpha 2, histamine H3 and somatostatin receptors to treatment of vascular headaches is suggested.
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PMID:UK-14,304, R(-)-alpha-methyl-histamine and SMS 201-995 block plasma protein leakage within dura mater by prejunctional mechanisms. 128 76

Studies of regional cerebral blood flow in migraine with aura have shown that the aura phase is associated with hypoperfusion in the cortical area which relates topographically to the clinical symptoms. Thus, the previously hypoperfused area becomes hyperperfused. However, there is no strict association between hyperperfusion and headache. The mode of hypoperfusion propagation recalls the circulatory manifestations of experimental cortical spreading depression. In addition, there are no focal cerebral blood flow abnormalities in migraine without aura. During the headache phase of migraine, dilation of both the large extra- and intracranial arteries takes place. A bulk of biochemical evidence has suggested that the pain in migraine is caused by blood vessels which are dilated and sensitized by circulating pain-producing substances e.g. bradykinin, serotonin and histamine (sterile inflammation). Recently, perivascular trigeminal fibres (trigeminovascular system) which, when stimulated, release sensory peptides (substance P and the calcitonin gene-related peptide) capable of provoking marked vasodilation and plasma extravasation (neurogenic inflammation) have been identified. Thus, the activation of the trigeminovascular system is probably involved in the vasodilatative and nociceptive phenomena of the migraine attack. The finding of a reduced endorphinergic brain tonus in migraine patients supports the hypothesis of a central nociceptive derangement in migraine. Nonetheless, the exact relationship between vasodilation and headache remains to be defined. However, the potent antimigraine effectiveness of sumatriptan--an agonist of the serotonin receptors which selectively constricts dilated arteries during the migraine attack--once again stresses the fact that serotonin is probably the crucial factor in the link between vasodilation and headache.
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PMID:[The pathogenetic bases of hemicrania]. 129 98

The vasoreactivity of the intracranial segment of the internal carotid artery to transmitters, present in the perivascular sympathetic, parasympathetic and sensory nerves, as well as to other vasoactive agents of relevance for headache, was tested in man and monkey. The total arterial segment from both species is equipped with contractile receptors for noradrenaline, serotonin, prostaglandin F2 alpha, ergotamine and sumatriptan. Further, the total arterial segment dilated upon exposure to calcitonin gene-related peptide in both species. Other vascoactive transmitters, acetylcholine, substance P and neurokinin A, caused only weak dilatation, restricted to the proximal extracavernous segment in the monkey. The findings are discussed in relation to the pathogenesis and treatment of cluster headache.
Cephalalgia 1992 Oct
PMID:Vasoreactivity of the intracranial internal carotid artery. 135 56

The absolute indomethacin effect in some unilateral headaches may, at least partially, be cyclooxygenase inhibition-independent. Aspirin and indomethacin, for example, may inhibit the neurogenically induced plasma extravasation in rat dura mater. Given the putative involvement of trigeminal neuropeptides in the pathophysiology of these conditions, the influence of cyclooxygenase inhibitors (indomethacin, acetylsalicylic acid (ASA) and naproxen) has been studied upon substance P, calcitonin gene-related peptide and vasoactive intestinal peptide (VIP)-induced vasodilatation in PGF2 alpha precontracted porcine ophthalmic arteries in vitro. None of the cyclooxygenase inhibitors significantly altered the effects of calcitonin gene-related peptide. The 10(-10) mol/l VIP-induced relaxation was inhibited significantly by all three cyclooxygenase inhibitors. Substance P-induced relaxation (from 10(-10) to 10(-8) mol/l) was enhanced by ASA and inhibited both by naproxen and, to a lesser extent, by indomethacin. The results suggest mainly that VIP-induced relaxations, particularly at lower concentrations, may be inhibited by all three cyclooxygenase inhibitors, and that naproxen, to a greater extent than aspirin or indomethacin, showed a tendency to inhibit vasodilatation induced by all peptides.
Cephalalgia 1992 Feb
PMID:Cyclooxygenase inhibitors modify the relaxant effect of vasoactive intestinal polypeptide and substance P in isolated porcine ophthalmic artery. 137 9

Lithium is currently a major drug used as a treatment for affective disorders and cluster headache, among other conditions. Its mechanism of action remains unknown. The trigeminovascular system may be involved in the pathophysiology of cluster headache and related diseases by liberating neuropeptides such as substance P (SP) and calcitonin gene-related peptide (CGRP) in the eye-forehead region. The objective of this study was to investigate whether or not a low concentration of lithium may interfere with peptidergic neuro-transmission at this level. Vasoactive intestinal peptide (VIP), SP, CGRP, capsaicin, and SP+CGRP concentration-response relaxation curves were obtained in the presence and absence of 2 x 10(-4) M lithium in isolated porcine ophthalmic arteries. Lithium inhibited the SP and VIP, but not the CGRP responses. Capsaicin-(a neurotoxin causing release of stored sensory neuropeptides) induced relaxations were partially inhibited by lithium. It is concluded that lithium may interfere with SP- and VIP-induced relaxation. If SP and VIP are of pathogenic significance in cluster headache, lithium may possibly work by counteracting unwanted effects of such peptides.
Headache 1992 Jul
PMID:Lithium inhibits substance P and vasoactive intestinal peptide-induced relaxations on isolated porcine ophthalmic artery. 138 46

Although it is known that pain in the forehead may be induced by neck abnormalities, the actual neck-head connections responsible for development of pain in trigeminal areas are poorly understood. Vasoactive neuropeptides released from sensory fibres, such as substance P (SP) and calcitonin gene-related peptide (CGRP), have been considered as important elements in headache pathophysiology. The levels of CGRP-like immunoreactivity (LI) were measured bilaterally in the jugular blood (52 rats) and intraocular aspirates (66 rats) following electrical stimulation of the left greater occipital nerve, and in the jugular blood of 13 control animals. One-third of the stimulated rats had varying combinations of conjunctival injection, tearing, diminished eye aperture and miosis or mydriasis on the stimulated side. The other two-thirds exhibited no ocular signs. Significantly lower levels of CGRP-LI were present in the jugular blood on the stimulated side in comparison with control rats. There was comparatively lower CGRP-LI on the non-stimulated side as well, but to a lesser extent. Significant differences between the stimulated and the non-stimulated side were present, particularly in the tearing/diminished eye cleft group. It is proposed that stimulation of the rat GON inhibits the trigeminal system (reduction of CGRP-LI) and possibly activates parasympathetic fibres (ocular changes).
Cephalalgia 1992 Oct
PMID:Reduction of calcitonin gene-related peptide in jugular blood following electrical stimulation of rat greater occipital nerve. 142 57

A patient is described with a 17-year history of intractable left-sided facial pain. The pain occurred daily in 5 sec spasms to a maximum of one every 2-3 min and was restricted to the left upper face. It was associated with rhinorrhoea on the left and often with ipsilateral facial flushing. Conventional therapy, including carbamazepine, baclofen and three posterior fossa explorations, had not provided lasting relief. Local facial stimulation by tapping a painful trigger point led to both pain and flushing of the face ipsilaterally. During this flushing, blood was collected and assayed using sensitive radioimmunoassays for several neuropeptides (neuropeptide Y, substance P, vasoactive intestinal polypeptide and calcitonin gene-related peptide). A marked (119%) increase in calcitonin gene-related peptide was noted in the external jugular vein blood ipsilaterally during the flushing with no change in the other peptides measured. To quantitate the effect of calcitonin gene-related peptide on human extracranial vessels, standard pharmacological procedures were used to examine the potency of the peptide as a vasodilator of human facial artery. The IC50 of calcitonin gene-related peptide for the prostaglandin F2 alpha-precontracted human facial artery was 10(-9) mol/l. The relevance of these observations to the clinical problem of migraine is considered.
Cephalalgia 1992 Feb
PMID:Cutaneous sensory stimulation leading to facial flushing and release of calcitonin gene-related peptide. 155 59

The spinal accessory nerve has been generally thought to be a cranial nerve with purely motor function, innervating the trapezius and sternocleidomastoid muscles. The present study identified clusters of sensory neurons consistently associated with this cranial nerve in adult rats. Either a single microganglion or several dispersed microganglia were found that adhered to the spinal root of the nerve, to small vessels, or were free within the subarachnoid space. The neurons of the ganglion had axons that joined the spinal root of the nerve proximal to its exit from the skull. Additional branches appeared to have an intracranial distribution within the arachnoid of the brainstem and along its vessels. Several findings suggest that the function of the ganglion is sensory and not autonomic. First, the architectural features of neurons within the ganglion (including their size, pseudounipolar morphology, and the lack of synaptic contacts) are similar to those of neurons in other sensory ganglia. Second, substance P and calcitonin gene-related peptide coexist within neurons of the microganglion, whereas markers for the major transmitters found in autonomic ganglia in rats are absent. Third, the expression of peptides in neurons of the ganglion was sensitive to neonatal capsaicin treatment. Finally, neurons within the ganglion were filled with a retrogradely transported dye after injection of the dye into the cervical spinal cord. Although the function of the ganglion is not known, its features are consistent with a role in nociception from the muscles of the spinal accessory complex, and it may be involved in headaches that have an occipital distribution.
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PMID:Detection and characterization of a sensory microganglion associated with the spinal accessory nerve: a scanning laser confocal microscopic study of the neurons and their processes. 167 15

These studies of cluster headache (CH) focus on two key features of pain transmission: a) sensory nerves when stimulated, as well as the expected afferent transmission, also display an efferent function which affects capillaries, glands, and smooth muscle (of the iris in CH); substance P (SP) and allied transmitters such as Vasoactive Intestinal Peptide (VIP) and Calcitonin Gene-Related Peptide (CGRP) are the main agonists of this dual afferent-efferent function; b) impaired pain transmission (deafferentation-like condition) provokes a rostral spread of neuronal irritability and automatic firing ("quasi epileptic foci") producing a clinical predilection for pain with the generation of "spontaneous" pains along the sensory pathways. The substrates studied in the present experiments are the iris, salivary glands, and nasal mucosa. 1) Iris: the conjunctival instillation of SP induces isocoric miosis both in CH sufferers and in normals, thus excluding gross SP receptoral dysfunction of the iris muscle in CH. Electrical stimulation of extraocular (infratrochlear) endings of the first branch of the trigeminal nerve provokes a miosis, which is significantly less in the symptomatic eye than in the contralateral one. This miosis is ascribed to a retrograde release of SP, induced by electrical stimulation of the trigeminal ophthalmic branch. The relatively poor miosis in the painful eye could correlate with a deficient release of SP from the sensory terminals in the iris. 2) Salivary glands: an increase of substance P-like immunoreactivity is found in the saliva taken from the asymptomatic side, but not from the painful side during a cluster headache attack, thus showing at this level also an asymmetry as previously shown in other head structures. 3) Nasal mucosa: intranasal application of capsaicin, a powerful releaser of SP from sensory terminals, evokes an immediate burning pain in the ipsilateral nasal, ocular, and temporal areas, as well as lacrimation and rhinorrhea. A gradual decrease (tachyphylaxis) of these phenomena is consistently observed after few days of daily nasal administration of capsaicin. When this treatment is applied to CH patients, a rapid decrease in the number and intensity of attacks, and even disappearance of symptoms accompanies the decline of the capsaicin-induced manifestations. Local (nasal) capsaicin, in spite of evoking immediately the same vegetative (rhinorrhea, lacrimation, conjunctival congestion) and in part nociceptive (transient nasal, ocular, temporal burning) phenomena of CH, never has been able to provoke delayed spontaneous-CH like attacks. Such delayed provoked attacks, one of the most pregnant phenomena in CH investigations, are almost constantly evoked by systemic stimuli.(ABSTRACT TRUNCATED AT 400 WORDS)
Headache 1990 Jan
PMID:Substance P theory: a unique focus on the painful and painless phenomena of cluster headache. 168 82


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