sumatriptan, Imitrex
Sumatriptan in the acute treatment of migraine without aura: efficacy of 50-mg dose.

Moschiano F, D'Amico D, Grazzi L, Leone M, Bussone G.

Headache Centre, Neurological Institute C Besta, Milano, Italy.

We conducted an open study on the efficacy of 50 mg of sumatriptan as an acute treatment for migraine without aura. We recruited 200 consecutive patients, with an established history of migraine without aura, presenting at a headache center. The patients were instructed to take half a 100-mg sumatriptan tablet for their next migraine attack, and to record details of their headache in a diary. The primary outcome of the study was headache relief from one migraine attack. Attacks were moderately intense (46%), moderate to severe (7%), or severe (47%). Total or partial benefit at 2 hours from the 50-mg dose was reported by 140 of 200 patients (70%). Thirty-six patients received no benefit from half a tablet, and 24 did not take sumatriptan, preferring their habitual medication. Side effects were few, mild, and short lasting. We conclude that the 50-mg oral dose is generally effective for migraine without aura attacks of both moderate and severe intensity and recommend this dose for all such patients. If, however, sumatriptan is ineffective at that dose it can be increased to a maximum of 100 mg.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9277024&dopt=Abstract sumatriptan Imitrex



sumatriptan, Imitrex
Effects of the 5-HT1 receptor agonists, sumatriptan and CP 93,129, on dural arterial flow in the rat.

Messlinger K, Hotta H, Pawlak M, Schmidt RF.

Department of Physiology, University of Wurzburg, Germany. karl.messlinger rzroe.uni-wuerzburg.de

The blood flow in and around the medial meningeal artery (dural arterial flow) was recorded in the exposed parietal dura mater encephali of the anesthetized rat using laser Doppler flowmetry. Local electrical stimulation of the dura mater (pulses of 0.5 ms delivered at 7.5-17.5 V and 5 or 10 Hz for 30 s) caused temporary increases in dural arterial flow. The effects of the 5-HT1 receptor agonists sumatriptan and CP 93,129 on the basal flow and the electrically evoked increases in flow were examined. Topical administration of undiluted sumatriptan (12 mg/ml) lowered the basal and the evoked flow by 20% on average. Systemic (i.v.) administration of sumatriptan (0.24, 0.72 and 3.6 mumol/kg) caused a short-lasting reduction of the evoked flow increases only at the higher doses while the basal flow was not significantly altered. Systemic administration of CP 93, 129 (0.46 and 4.6 mumol/kg) caused no significant changes of the basal and the evoked flow. At a dose of 23 mumol/kg CP 93,129 lowered the basal flow by 20% and the evoked flow by 30% for 20 min. The systemic arterial pressure was not significantly altered by sumatriptan and CP 93,129 within the whole range of doses. It is suggested that sumatriptan and CP 93,129 at high doses exert inhibitory effects on those fine afferent nerve fibers which release the calcitonin gene-related peptide, since this neuropeptide mediates the evoked increases in dural arterial flow.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9286619&dopt=Abstract sumatriptan Imitrex



sumatriptan, Imitrex
Characterization of sumatriptan-induced contractions in human isolated blood vessels using selective 5-HT(1B) and 5-HT(1D) receptor antagonists and in situ hybridization.

van den Broek RW, Bhalla P, VanDenBrink AM, de Vries R, Sharma HS, Saxena PR.

Department of Pharmacology, Erasmus University Medical Centre Rotterdam, Rotterdam, The Netherlands.

The 5-HT(1B/1D) receptor agonist sumatriptan is effective in aborting acute attacks of migraine and is known to cause constriction of cranial arteries as well as some peripheral blood vessels. The present study set out to investigate whether 5-HT(1B) and/or 5-HT(1D) receptors mediate contractions of the human isolated middle meningeal and temporal arteries (models for anti-migraine efficacy) and coronary artery and saphenous vein (models for side-effect potential). Concentration-response curves were made with sumatriptan (1 nm-100 microm) in blood vessels in the absence or presence of selective antagonists at 5-HT(1B) (SB224289) and 5-HT(1D) (BRL15572) receptors. SB224289 antagonized sumatriptan-induced contractions in all blood vessels, although the antagonism profile was different amongst these blood vessels. In the temporal artery, SB224289 abolished contraction to sumatriptan, whereas in the middle meningeal artery and saphenous vein sumatriptan-induced contractions were blocked in an insurmountable fashion. Moreover, SB224289 acted as a weak surmountable antagonist in the coronary artery (pK(B): 6.4 +/- 0.2). In contrast, BRL15572 had little or no effect on sumatriptan-induced contractions in the four blood vessels investigated. In situ hybridization revealed the expression of 5-HT(1B) receptor mRNA in the smooth muscle as well as endothelial cells of the blood vessels, whereas the mRNA for the 5-HT(1D) receptor was only very weakly expressed. These results show that the 5-HT(1B) receptor is primarily involved in sumatriptan-induced contractions of human cranial as well as peripheral blood vessels.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11972574&dopt=Abstract sumatriptan Imitrex



sumatriptan, Imitrex
Characteristics and determinants of sumatriptan-associated chest pain.

Ottervanger JP, Valkenburg HA, Grobbee DE, Stricker BH.

Netherlands Centre for Monitoring of Adverse Reactions to Drugs, Rijswijk, The Netherlands.

BACKGROUND: Serious cardiac adverse reactions, including myocardial infarction, have been attributed to the antimigraine drug sumatriptan succinate. Chest pain is considered to be a relatively common adverse reaction to sumatriptan. DESIGN: Postmarketing study. PATIENTS AND METHODS: The study was a part of a national cohort study on adverse reactions to sumatriptan, which was performed with the assistance of drug-dispensing general practitioners in the Netherlands. After data were collected on observed adverse reactions, the patients received a second questionnaire, with specific questions regarding the adverse event, and questions regarding medical history, other health complaints, and smoking habits. Furthermore, they had a physical examination and a blood cholesterol measurement. RESULTS: A total of 137 patients with chest pain associated with intake of sumatriptan were identified and compared with 229 consumers of sumatriptan without this adverse reaction. After multivariate analysis, young age, hypertension, general complaints of abdominal pain, and a family history of myocardial infarction were associated with an increased risk of chest pain attributed to sumatriptan. Hypertension in particular was a risk factor for sumatriptan-induced chest pain in men (relative risk, 8.0; 95% confidence interval, 1.8-40) compared with hypertension as a risk factor in women (relative risk, 1.63; 95% confidence interval, 0.9-3.1). CONCLUSIONS: Young age, hypertension, general complaints of abdominal pain, and a family history of myocardial infarction are associated with an increased risk of chest pain attributed to sumatriptan. Sex is an effective modifier of risk factors of sumatriptan-induced chest pain. In particular, hypertension is a strong risk factor in men.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9362987&dopt=Abstract sumatriptan Imitrex



sumatriptan, Imitrex
The selectivity of MDL 74,721 in models of neurogenic versus vascular components of migraine.

Petty MA, Elands J, Johnson MP, Linnik MD, Hamel E, Moskowitz MA, Lee WS, McCarty DR, Hibert M, Baron BM.

Marion Merrell, Strasbourg, France. petty21 lsgbw.hcc.com

MDL 74,721 (R)-2-(N1,N1-dipropylamino)-8-methylaminosulfonylmethyl-1,2,3,4-te trahydronaphthalene, a sulfonamidotetralin, has been found to exhibit a 10,000-fold greater potency in neurogenic versus vascular models of migraine. Sumatriptan, a relatively pure 5-HT1D/5-HT1B receptor agonist, also showed higher potency versus neurogenic inflammation. However, for sumatriptan the potency difference (100-fold) in the two pathophysiological models was less pronounced than seen for MDL 74,721. The affinity profile of MDL 74,721 at 5-HT1 receptor subtypes may in part explain its ability to differentiate these two physiological responses. MDL 74,721 demonstrated nanomolar affinity for 5-HT1A (12.7 +/- 0.3 nM) and 5-HT1D (41.3 +/- 10.9 nM) but considerably lower affinity for 5-HT1B receptors (> 1000 nM). Serotonin-like activity was seen in in vitro functional assays including inhibition of forskolin-stimulated cAMP accumulation in human 5-HT1D receptor-transfected fibroblasts or eliciting vasoconstriction in isolated human pial arteries. The intrinsic activity (relative to 5 - HT[E(Amax)]) and affinity (pD2) for the human cerebrovascular 5-HT receptors were: 5-HT (100%, 7.51 +/- 0.09), sumatriptan (94%, 6.85 +/- 0.1) and MDL 74,721 (66%, 5.70 +/- 0.23). In anaesthetised cats, treatment with MDL 74,721 resulted in a dose-related reduction in the percentage of carotid flow going through the arteriovenous anastomoses to the lungs, with an ED50 of 0.3 mg/kg i.v., the same as sumatriptan. However, in the guinea-pig neurogenic model, MDL 74,721 inhibited plasma protein extravasation with an ED50 of 0.023 microg/kg compared to 2.5 microg/kg for sumatriptan. MDL 74,721 was also effective in this model (in rats) after oral administration. In conclusion, MDL 74,721 demonstrates a preclinical profile consistent with anti-migraine efficacy. Its marked preference for inhibiting neurogenic inflammation makes this compound a useful tool for assessing the relative contribution of this pathophysiological mechanism to the human disease state.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9384224&dopt=Abstract sumatriptan Imitrex



sumatriptan, Imitrex
Involvement of central cholinergic system in antinociception induced by sumatriptan in mouse.

Ghelardini C, Galeotti N, Nicolodi M, Donaldson S, Sicuteri F, Bartolini A.

Department of Preclinical and Clinical Pharmacology, University of Florence, Italy.

The antinociceptive effect of the antimigraine drug sumatriptan was assessed in mice (hot-plate and abdominal constriction tests). Antinociception induced by sumatriptan (10-30 mg kg-1 i.p.) was prevented by the muscarinic antagonist atropine (5 mg kg-1 i.p.), the ACh-depletor hemicolinium-3 (1 microgram per mouse i.c.v.) and the 5-HT1A antagonist NAN-190 (0.5 mg kg-1 i.p.). Naloxone, CGP-35348 and reserpine administered in doses suitable for blocking analgesia respectively induced by morphine, baclofen and clomipramine did not modify sumatriptan antinociception. On the basis of the above findings, we can deduce that sumatriptan was able to induce antinociception by increasing cholinergic neurotransmission through the stimulation of 5-HT1A receptors.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9403365&dopt=Abstract sumatriptan Imitrex



sumatriptan, Imitrex
Characterization of 5-HT receptors on human pulmonary artery and vein: functional and binding studies.

Cortijo J, Marti-Cabrera M, Bernabeu E, Domenech T, Bou J, Fernandez AG, Beleta J, Palacios JM, Morcillo EJ.

Departament de Farmacologia, Facultad de Medicina i Odontologia, Universitat de Valencia, Spain.

1. This study aimed to investigate the 5-hydroxytryptamine (5-HT) receptors mediating contraction of ring preparations isolated from human pulmonary arteries and veins. In functional studies, the responses to 5-HT, sumatriptan, ergotamine, serotonin-O-carboxymethyl-glycyl-tyrosinamide (SCMGT), alpha-methyl 5-HT (alpha-Me) and 2-methyl 5-HT (2-Me) were studied with WAY100635, GR127935, ritanserin, zacopride and SB204070 as antagonists. 2. All agonists produced concentration-dependent contractions of human pulmonary artery and vein preparations. The order of potency (-log ECS0 values) was ergotamine (6.88) > 5-HT (6.41) > or = SCMGT (6.20) = sumatriptan (6.19) > or = alpha-Me (6.04) in the artery, and ergotamine (7.84) > 5-HT (6.96) > sumatriptan (6.60) = alpha-Me (6.56) > SCMGT (6.09) in the vein. The potency of each agonist, except for SCMGT, was greater in vein than in artery preparations. Contractile responses to 5-HT were similar in intact and endothelium-denuded preparations but responses to sumatriptan were enhanced in artery rings without endothelium. 3. GR127935 (1 nM to 0.5 microM) produced an unsurmountable antagonism of the response to 5-HT, sumatriptan, ergotamine and SCMGT. Ritanserin (1 nM to 1 microM) also reduced the maximum contractile responses to 5-HT, ergotamine and alpha-Me in artery and vein preparations without affecting those to sumatriptan and SCMGT. In endothelium-denuded preparations, surmountable antagonism of sumatriptan by GR127935 (in the presence of ritanserin) and of alpha-Me by ritanserin (in the presence of GR127935) allowed for the calculation of the apparent pK(B) values of GR127935 (9.17+/-0.11 in artery and 9.11+/-0.05 in vein) and ritanserin (8.82+/-0.09 in artery and 8.98+/-0.12 in vein). 4. WAY100635 (1 nM to 1 microM), zacopride (1 nM to 1 microM), or SB204070 (1 nM) did not significantly alter the concentration-response curves for 5-HT, sumatriptan, ergotamine, SCMGT or 2-Me in human pulmonary artery or vein thus indicating that 5-HT1A, 5-HT3 and 5-HT4 receptors are presumably not involved in the contractile response to these agonists. 5. Binding studies using selective radioligands for different 5-HT receptors could not detect the presence of 5-HT1A receptor binding in human pulmonary blood vessels whereas the 5-HT(1B/1D) radioligand [3H]-5CT significantly labelled a population of specific binding sites in both vessel types. The presence of 5-HT2A receptors could also be inferred from the level of binding of [3H]-ketanserin to membranes obtained from human pulmonary vessels, although significance could not be reached for arteries. 5-HT4 specific receptor binding was scarce in veins and absent in the case of arteries. 6. These findings indicate that the human pulmonary artery and vein have a mixed functional population of 5-HT(1B/1D) and 5-HT2A receptors mediating the contractile response to 5-HT which is consistent with results of the binding studies.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9421295&dopt=Abstract sumatriptan Imitrex