Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018681 (headache)
 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serotonin (5-Hydroxytryptamine) seems to play a dominant role in triggering vomiting induced by cytotoxic agents through the stimulation of 5-HT3 receptors. They have been observed in the GI tract as well as in the brain (area postrema). Ondansetron is a specific antagonist of 5-HT3 serotonin receptors. Its anti-emetic activity is very powerful in the ferret. The availability of an injectable or oral form of this product allows the overall treatment of acute and delayed emesis and its administration is in accordance with different schedules: single IV injection or a continuous 24 hour infusion or repeated IV injection followed by oral treatment. The pharmacokinetics of the drug are as follows: absorption begins about 30 minutes after the administration per os, its biodisponibility is about 60%, its clearance: 20 ml/minute and its elimination half life about 3 hours. Different double blind studies, carried out in parallel groups or in cross over, demonstrated the superiority of ondansetron over metoclopramide in the control of nausea and vomiting, whether or not the chemotherapy contained cisplatin; a more recent study shows also that ondansetron was superior to alizapride and methylprednisolone in combination. Side effects of ondansetron do not include extrapyramidal symptoms but only headaches and constipation. The use of ondansetron improves the well-being of patients receiving chemotherapy and increases protocol compliance.
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PMID:[Ondansetron: a specific 5-HT3 serotonin receptor inhibitor, a new antiemetic in oncology]. 183 90

In an open, drug-oriented phase-II/III-study 24 patients were treated with the 5-HT3-antagonist Ondansetron as an antiemetic drug for chemotherapy-induced nausea and emesis. Patients with treatment regimen containing cisplatin were excluded. All patients had suffered from severe nausea and vomiting under conventional antiemetic drugs during a previous identical chemotherapy cycle and were treated with 8 mg Ondansetron t.d. on the day of the chemotherapy and on the four following days. The drug was given with 90 cytostatic cycles ranging from 1 to 14 cycles per patient. Only 2 patients (8%) did not experience an improvement of their symptoms in any of the treatment cycles as measured by a self-conducted grading of nausea and by the frequency of vomiting in comparison to a previous treatment cycle under conventional antiemetic therapy. Eleven out of 18 patients, who were treated with Ondansetron more than once (61%) noted a diminished frequency of vomiting in each treatment cycle with Ondansetron. Sixty of the 90 therapy cycles with Ondansetron resulted in complete (no vomiting) or major (one to two vomits within 24 h following chemotherapy) protection from emesis (37 and 29 per cent, respectively). The most frequent side effect noted was obstipation (7 patients), followed by slight diffuse abdominal pain (4 patients, probably also due to chemotherapy) and slight to severe headache (3 patients, 1 patient was therefore withdrawn from the study). No other side effects were seen. In conclusion, our study indicates that Ondansetron is an effective and safe drug for the treatment of cytostatic drug-induced nausea and vomiting.
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PMID:[Ondansetron (GR 38032F), a competitive 5-HT3 receptor antagonist as an antiemetic in cytostatic drug-induced nausea and vomiting. An open, substance-oriented phase II/III study]. 215 May 52

GR38032F is a specific 5-HT3 (serotonin) receptor antagonist with antiemetic activity in animal and early human studies. We performed a dose-ranging phase I study of GR38032F in 43 evaluable patients receiving cisplatin 60 120 mg/m2 for the first time (38 of these patients were chemotherapy-naive). Intravenous GR38032F was administered over a dose range from 0.01 to 0.48 mg/kg given three times at four-hour intervals beginning one half hour before cisplatin, and patients were observed for 24 hours. An additional five patients were treated with 0.18 mg/kg given three times at six-hour intervals. Excellent antiemetic efficacy was noted, with 44% of patients experiencing no vomiting and 26% no nausea. Major protection from vomiting (less than or equal to 2 episodes) and from nausea (less than or equal to 2 hours) was experienced by 81% and 44%, respectively. Mild to moderate headache (40%), lightheadedness (21%), and elevated transaminase (19%) were the most common adverse events reported. One patient experienced an apparent hypersensitivity reaction that responded to conventional medications. No extrapyramidal reactions or akathisia were seen. GR38032F was effective through most of the dose range. However, efficacy decreased at the 0.01 mg/kg level and number and intensity of adverse events increased at the 0.48 mg/kg level. Analysis of those patients receiving high-dose cisplatin (100 to 120 mg/m2) revealed a positive association of GR38032F dose and antiemetic activity (Fisher's exact test, two-sided; P less than .05). The 5-HT3 receptor antagonists may provide antiemetic efficacy similar to high-dose metoclopramide without antidopaminergic toxicity. The maximum recommended dose on this schedule of GR38032F is 0.36 mg/kg.
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PMID:Dose ranging phase I study of the serotonin antagonist GR38032F for prevention of cisplatin-induced nausea and vomiting. 252 64

This paper reports part of a study which investigated the identity of the receptor involved in 5-hydroxytryptamine (5-HT) mediated contraction of the human basilar artery in vitro. 5-HT and a variety of 5-HT receptor agonists contracted human isolated basilar artery with a rank order of agonist potency: 5-carboxamidotryptamine greater than 5-HT greater than GR43175 much much greater than 2-methyl-5-HT. The maximum response produced by these agonists differed. The contractile responses to both 5-HT and GR43175 were resistant to antagonism by the 5-HT2 antagonist ketanserin and the 5-HT3 antagonist GR38032, indicating that neither 5-HT nor GR43175 activate 5-HT2 and 5-HT3 receptors in this tissue. In striking contrast, methiothepin (an antagonist at 5-HT1-like receptors) proved a potent antagonist of the contractile actions of both 5-HT and GR43175. Methiothepin did not antagonize the contractile response to the thromboxane-A2 mimetic U-46619. It is concluded that 5-HT and GR43175 contract the human isolated basilar artery by activating 5-HT1-like receptors. It is suggested that the antimigraine action of GR43175 may reflect its ability to constrict certain cranial arteries via 5-HT1-like receptor activation.
Cephalalgia 1989
PMID:Characterization of the 5-hydroxytryptamine receptor which mediates contraction of the human isolated basilar artery. 254 83

The potency of dihydroergotamine (DHE) was determined at 13 neurotransmitter receptors using radioligand binding techniques. DHE is a potent agent (i.e. affinity value less than 100 nM) at 5-hydroxytryptamine1A (5-HT1A), 5-HT1C, 5-HT1D, 5-HT2, dopamine2, alpha1- and alpha2-adrenergic binding sites. DHE displays moderate affinity (i.e. affinity values = 100 - 1000 nM) for beta-adrenergic and dopamine1 sites and is completely inactive at 5-HT3, muscarinic and benzodiazepine receptors. These results were then compared to similar data on sumatriptan (formerly called GR 43175), a novel acute anti-migraine agent. The only pharmacological property shared by both agents is high affinity for 5-HT1D and 5-HT1A receptors. Therefore, these data suggest that 5-HT1D and/or 5-HT1A receptors may play an important role in the pathophysiology of migraine.
Headache 1989 Jul
PMID:Comparative neuropharmacology of dihydroergotamine and sumatriptan (GR 43175). 254 33

The availability of selective compounds has made it possible to subdivide 5-hydroxytryptamine (5-HT) receptors into three distinct types, called 5-HT1-like, 5-HT2 and 5-HT3. The selective agonists at the three receptor types are, respectively, 5-carboxamidotryptamine, alpha-methyl-5-HT and 2-methyl-5-HT. While no selective antagonists are yet available for the 5-HT1-like receptors, some compounds, including ketanserin and MDL 72222, selectively antagonize 5-HT2 and 5-HT3 receptors respectively. Depending upon experimental conditions, 5-HT causes a constriction or dilatation of cerebral and extracerebral cranial vessels. Vascular contraction by 5-HT seems to be mediated primarily via 5-HT2 receptors (located mainly on large conducting vessels), though in several instances (for example, dog and human basilar arteries and porcine arteriovenous anastomoses; AVAs) 5-HT1-like receptors are involved in addition to or in place of 5-HT2 receptors. In the rabbit ear and external carotid arteries 5-HT may act directly on alpha-adrenoceptors. Arteriolar dilatation, leading to increased capillary ("nutrient") blood flow, occurs via 5-HT1-like receptors. However, the 5-HT1-like receptors on the arterioles and AVAs appear to be similar but not identical. Since a reduction of plasma 5-HT and opening of AVAs have been implicated in the pathophysiology of migraine, compounds acting on 5-HT1-like receptors to close the shunt vessels can be expected to have therapeutic activity in migraine.
Cephalalgia 1989
PMID:Characterization of 5-hydroxytryptamine receptors in the cranial vasculature. 266 Oct 12

GR-C507/75 (GR38032F) antagonizes the 5-HT3 (serotonin) receptor and prevents cisplatin-induced emesis in animals. In this dose-ranging trial, 44 patients with cancer receiving chemotherapy known to produce nausea and vomiting (including cisplatin, cyclophosphamide, and doxorubicin) received three intravenous (IV) infusions of GR-C507/75 every two hours beginning 30 minutes before chemotherapy. Ten dosage levels were explored, ranging from 0.04 mg/kg to 0.35 mg/kg in each of the three infusions. Toxicities were mild and included sedation, dizziness, headache, transient elevations of SGOT or alanine aminotransferase (ALT), and dry mouth. No akathisia or acute dystonic reactions were observed. Antiemetic effects were seen in patients receiving cisplatin at 120 mg/m2. GR-C507/75 can be safely administered on this schedule at IV dosages up to 0.35 mg/kg in patients receiving chemotherapy. Further studies of this agent at higher dosages and by different schedules are appropriate.
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PMID:Dose-ranging evaluation of the serotonin antagonist GR-C507/75 (GR38032F) when used as an antiemetic in patients receiving anticancer chemotherapy. 296 55

Tropisetron is a potent and selective serotonin 3 (5-hydroxytryptamine3; 5-HT3) receptor antagonist with antiemetic properties, probably mediated via antagonism of receptors both at peripheral sites and in the central nervous system. When compared with antiemetic regimens containing high-dose metoclopramide in a small number of studies, tropisetron was generally as effective at preventing acute and delayed vomiting induced by high-dose cisplatin (> or = 50 mg/m2). In these studies tropisetron completely prevented vomiting occurring in the first 24 hours after chemotherapy in 35 to 76% of patients. Tropisetron was superior to alizapride in preventing emesis induced by high-dose alkylating agents. The effectiveness of tropisetron in patients who had previously had partial control of emesis was improved by the addition of dexamethasone. Tropisetron appears to be well tolerated with the most frequently reported adverse effect being headache. Extrapyramidal effects, which can occur in 5 to 10% of patients receiving high-dose metoclopramide and which may limit its use, have been reported in only isolated cases with tropisetron. Thus, tropisetron is an effective, apparently well tolerated agent which can be administered once daily for the prevention of chemotherapy-induced nausea and vomiting. However, further clinical experience is needed to clarify the optimum role of tropisetron as an antiemetic agent, particularly with regard to other drugs in its class. Nonetheless, preliminary results indicate that tropisetron will be a useful alternative for use in controlling emesis induced by cytotoxic therapy.
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PMID:Tropisetron. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential as an antiemetic. 750 39

Granisetron is a selective serotonin3 (5-hydroxytryptamine3, 5-HT3) receptor antagonist which has significant antiemetic activity against chemotherapy-induced nausea and vomiting. A single prophylactic intravenous dose is sufficient to control acute nausea and vomiting in approximately 60 to 70% of patients. In comparative studies, the acute antiemetic efficacy of granisetron is equivalent or superior to that of traditional antiemetic regimens even in patients receiving highly emetogenic cisplatin-containing chemotherapy. However, limited data have suggested that granisetron therapy offers no advantages over traditional antiemetics in terms of the control of delayed emesis. Recently, a number of large randomised studies have directly compared the efficacy and tolerability of granisetron, ondansetron and tropisetron and reported no significant differences between the 3 drugs in controlling acute nausea and vomiting, although 1 study reported a modest statistical advantage for granisetron over ondansetron but not tropisetron in the complete control of vomiting. In crossover studies, significantly more patients preferred granisetron to either ondansetron or tropisetron. The efficacy of granisetron appears to be maintained with repeated doses over several cycles of chemotherapy, although the influence of various prognostic factors affecting antiemetic response has not been adequately analysed. Concomitant administration of dexamethasone significantly improves the acute antiemetic efficacy of granisetron, increasing response rates by approximately 15%. Granisetron is an effective antiemetic in children undergoing highly emetogenic chemotherapy, and effectively controls radiotherapy-induced and postoperative nausea and vomiting. Trials using an oral formulation are scarce at present, but preliminary results suggest a similar efficacy and tolerability profile to that of the intravenous formulation. Granisetron has been well tolerated in clinical trials. The most frequently reported adverse event has been headache (14%). Extrapyramidal effects, which can limit the use of traditional antiemetics such as metoclopramide, have not been reported with granisetron. Thus, recent data confirm that granisetron is an effective and well tolerated agent for the prophylactic treatment of chemotherapy-induced acute nausea and vomiting, with efficacy equivalent or superior to that of other currently available agents. It has a promising role to play in paediatric oncology, and is an effective agent in controlling radiotherapy-induced acute emesis. Granisetron offers comparable or superior efficacy in controlling acute nausea and vomiting with a much simpler dosage regimen than that of traditional antiemetic regimens.
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PMID:Granisetron. An update of its therapeutic use in nausea and vomiting induced by antineoplastic therapy. 753 Jun 31

This review shows that the role of 5-hydroxytryptamine (5-HT) in the regulation of nociception depends on the 5-HT receptor subtypes involved and on long-term functional changes in the 5-HT receptors. Stimulation of the 5-HT1 receptors, as well as of the 5-HT2 and 5-HT3 receptors, may reduce nociceptive sensitivity. In addition, activation of 5-HT2 and 5-HT3 receptors may also enhance nociceptive sensitivity. Up- or down-regulation of the 5-HT receptors may result in long-lasting changes, plasticity, in the 5-HT systems. Lesioning of 5-HT neurons induces denervation supersensitivity to 5-HT, and prolonged stimulation of 5-HT receptors may produce subsensitivity to 5-HT. In the spinal cord denervation supersensitivity to 5-HT may depend on reduced release of substance P (SP). An increase in the release of SP, on the other hand, may reduce the effects of 5-HT receptor activation. Long-term treatment with antidepressants which are used in clinical pain therapy appears to up-regulate the 5-HT1 receptors and to down-regulate the 5-HT2 receptors.
Cephalalgia 1993 Apr
PMID:The role of 5-hydroxytryptamine (5-HT) receptor subtypes and plasticity in the 5-HT systems in the regulation of nociceptive sensitivity. 768 23


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