Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042963 (vomiting)
 31,883 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

5-HT3 receptor antagonists such as ondansetron, granisetron, ICS205-930 and zacopride are highly effective in the ferret, cat or dog to prevent emesis caused by cisplatin and other chemotherapeutic agents, and radiation treatment. The anti-emetic effects may be mediated centrally in the area postrema and associated structures of the emetic reflex such as the nucleus tractus solitarius, which have a very high density of 5-HT3 receptors. Additional sites of action may be found on the 5-HT3 receptors located on the vagus nerve or enteric neuronal elements in the gastro-intestinal tract. The precise site(s) and mechanism(s) of action of different cytotoxic treatments to induce emesis remains to be determined, but appears to involve a common action on a 5-HT3 system. The 5-HT3 receptor antagonists do not impair normal behaviour and, in particular, fail to affect the extrapyramidal motor system and do not cause sedation. Of potential benefit, the 5-HT3 receptor antagonists have an anxiolytic profile of action in rodent and primate models. The 5-HT3 receptor antagonists are revealed as an important group of drugs to prevent emesis induced by a wide range of cytotoxic treatments.
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PMID:Neuropharmacology of emesis in relation to clinical response. 146 94

In the present study, the emetic effect of the anticancer drug cisplatin, and protective effects of 5-HT3 receptor antagonists against cisplatin emesis were investigated in the pigeon. The experimental setting involved the i.v. administration of drugs and subsequent observation of the percentage of vomiting animals and number of emetic episodes per vomiting animal over a period of 5 h. In some experiments, the 5-HT and 5-HIAA content in tissues was estimated by the HPLC technique. It was observed that cisplatin (2.5-10 mg/kg) is able to induce dose-dependent emesis in the pigeon. 5-HT3 receptor antagonists (500 micrograms/kg) afford partial protection against cisplatin emesis, although some of them, i.e. indolic derivatives and zacopride, display intrinsic emetic activity at doses of 50-500 micrograms/kg. A serotonergic mechanism appears to be involved in both cisplatin- and 5-HT3 receptor antagonist-induced emesis, since pretreatment with an inhibitor of 5-HT synthesis, para-chlorophenylalanine (300 mg/kg x 3 days), is able to hamper vomiting induced by either cisplatin or 5-HT3 receptor antagonists. It is concluded that the intrinsic emetic effects of 5-HT3 receptor antagonists in the pigeon provide pharmacological evidence of species differences in the properties of 5 HT3 receptors.
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PMID:A dual effect of some 5-HT3 receptor antagonists on cisplatin-induced emesis in the pigeon. 147 Dec 30

This study was carried out to assess the efficacy of oral ondansetron, a new 5HT3 receptor antagonist, in patients undergoing thyroid surgery. It included 60 patients, randomly assigned to two groups, and receiving orally, 1 h before induction of anaesthesia, either 8 mg of ondansetron (n = 29) or a placebo (n = 30). One patient was excluded. The same anaesthetic protocol, consisting of 3 to 5 micrograms.kg-1 of fentanyl, 4 to 6 mg.kg-1 of thiopentone, and 0.5 mg.kg-1 of atracurium, was used in all. Anaesthesia was maintained with 50% nitrous oxide in oxygen with 0.8 to 1% endtidal concentration of isoflurane and additional boluses of 0.1 mg of fentanyl as required. The incidence and intensity of nausea, graded mild, moderate or severe, and the incidence of vomiting were recorded postoperatively. During the first twelve hours after surgery, 40% of patients in the placebo group had nausea (16.7% mild, 20% moderate and 6.7% severe), and 50% vomited. In the ondansetron group, nausea and vomiting occurred in 13.8% and 20.4% of patients respectively. The 4 patients in the latter group complained of major nausea. The differences between the groups were statistically significant: p = 0.025 for nausea and p = 0.042 for vomiting. It is concluded that oral ondansetron, 8 mg taken orally 1 h before surgery, significantly reduces the incidence of nausea and vomiting during the first twelve postoperative hours. As it is easy to use and has no side-effects, it might be of interest in day-case surgery patients, despite its high cost.
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PMID:[Prevention of postoperative nausea and vomiting by ondansetron]. 147 80

The incidence, severity, and onset of radiation-induced emesis (RIE) are related to field size, site, and dose per fraction. Radiation-induced emesis can occur (1) within 2 to 3 weeks in approximately 50% of patients after conventional fractionated radiotherapy (200 cGy/fraction) to the upper abdomen, (2) acutely in more than 90% of patients receiving fractionated total body irradiation (TBI) for bone marrow transplantation, and (3) within 30 to 60 minutes in more than 80% of patients following single high-dose (> 500 cGy)/large field hemibody irradiation (HBI). The increased frequency of emesis associated with TBI and HBI has renewed the interest in the mechanism and treatment of RIE. A number of studies have reported a significant difference in the incidence of emesis following doses of > or = 500 cGy to the upper-mid (> 80%) and lower (20% to 40%) hemibody. The data suggested that the organ responsible for emetic response was in the upper abdomen. However, the mechanism of RIE is not well understood, although degradation products from normal tissues and tumor have been suggested. The introduction and effectiveness of the 5-hydroxytryptamine3 receptor antagonists in chemotherapy-induced emesis and the location of these receptors in the upper abdomen (possible site of the radiation-associated emetic response) suggested that this group of compounds may have a role in RIE. Lucraft and Palmer (Clin Radiol 33:621-622, 1982) reported no differences between levonantradol and chlorpromazine in preventing RIE in patients treated with single doses of more than 10 Gy to a small upper abdominal field. Priestman (Eur J Cancer Clin Oncol 25:529-533, 1989 [Suppl]) reported on a pilot and randomized study with ondansetron after single doses of 8 to 10 Gy to the upper abdomen. In the pilot study, ondansetron achieved major or complete control of vomiting in 77% to 90% of patients; subsequently, he reported a significant difference between ondansetron (97%) and metoclopramide (45%) in controlling RIE on the day of radiotherapy. Hewitt et al (Bone Marrow Transpl 7:431-433, 1991) reported a complete or major response on 93% of the days of ondansetron therapy during pretreatment therapy with cyclophosphamide and TBI for bone marrow transplantation. A preliminary analysis of 41 patients treated with HBI at the Rex Cancer Center confirms the role of ondansetron in RIE. Twenty-eight patients (upper-mid 16 patients/lower HBI 12 patients) did not receive pretreatment antiemetics (group A); seven received non-ondansetron pre-HBI (group B); and six received ondansetron (group C).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Radiation-induced emesis: effects of ondansetron. 148 81

Tropisetron, a 5-HT3 receptor antagonist, was evaluated as antiemetic prophylaxis during postoperative abdominal irradiation of ovarian carcinoma patients. Twenty consecutive women with Stages I-III (FIGO) epithelial ovarian carcinomas were included. At the start of radiotherapy all patients were clinically tumor-free. Twelve women received irradiation on whole-abdominal fields, 1.0 Gy per fraction, during 6 weeks. Eight women were irradiated on the lower abdomino-pelvic fields, 1.7 Gy per fraction, during 5 weeks. Efficacy and adverse events were recorded by the patients in diary-form booklets using visual analog scales (VAS). All patients completed the treatment series and none was lost to follow-up. Nausea, generally mild (mean 20 mm VAS) and of short duration, increased from start (30%) to end of radiotherapy (54%). Episodes of vomiting were few in number and occurred in less than 10% of the cases. Diarrhoea was common towards the end of the radiotherapy courses, especially when the dose per fraction was 1.7 Gy and the need for extra antidiarrhoeal medication (loperamide) increased from 38% at the start to 100% at the end. The mean weight loss was only 1.2 kg during 5-6 weeks. The overall ratings for quality of life were excellent or good in 75-85% of the cases. The efficacy of tropisetron was rated excellent or good in 80% of the cases and the tolerability likewise in 85% in the overall evaluation of the drug made by the investigator. Tropisetron therefore seems to be a promising and well-tolerated drug in conjunction with extended radiotherapy on the whole- or lower-abdominal fields.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Tropisetron, a new 5-HT3 receptor antagonist, in the prevention of irradiation-induced nausea, vomiting and diarrhoea. 148 16

5-HT3 receptor antagonists, ondansetron, granisetron and tropisetron are highly specific for the 5-HT3 receptor and have a selectivity ratio of approximately 1000:1 compared with affinities for other receptors. Other 5-HT3 receptor antagonists, largely those having a benzamide structure, are non-selective. These include metoclopramide, renzapride and zacopride which stimulate gastric motility via activation of 5-HT4 receptors; metoclopramide is also a potent dopamine receptor antagonist. Selective 5-HT3 receptor antagonists are a major advance in the treatment of chemotherapy- and radiotherapy-induced emesis in cancer patients. These agents inhibit emesis by blocking 5-HT3 receptors on vagal afferent nerve terminals in the gastrointestinal mucosa and on terminals on the same vagal nerves in the vomiting system. Inhibition of acute emesis appears to be produced by blocking the initiation of the emetic reflex induced via 5-HT3 receptors and by 5-HT released from enterochromaffin cells in the small intestine, as well as by blocking 5-HT3 receptors in the hindbrain vomiting system.
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PMID:Selectivity of 5-HT3 receptor antagonists and anti-emetic mechanisms of action. 152 96

RB 6145, the ring-opened analog of RSU 1069, and PD 130908, the desoxy ring-opened analog of RSU 1069, were compared to RSU 1069 for their emetic potential in dogs. When RB 6145 and PD 130908 were administered intravenously at doses ranging from 20% to 50% of the mouse equivalent maximum tolerated dose (MTD), both analogs were less emetic than RSU 1069 on a molar basis. Furthermore, the 5HT3 antagonist ondansetron prevented emesis at doses as high as 75% of the MTD. The reactivity, and hence the emetic liability of these compounds, is thought to be mediated by formation of the corresponding aziridine intermediate. In mouse plasma, both analogs rapidly converted to two products, the reactive aziridine and a stable oxiazolidinone species formed upon reaction with bicarbonate in the blood. A positive correlation exists between the amounts of aziridine formed by these analogs and their emetic potential.
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PMID:Pharmacologic/pharmacokinetic evaluation of emesis induced by analogs of RSU 1069 and its control by antiemetic agents. 153 Dec 13

Ondansetron, a selective 5HT3 (serotonin) antagonist, was used in patients refractory to standard antiemetics. Seventy-five patients receiving chemotherapy without cisplatin were given ondansetron 4 mg IV and 4 mg orally immediately prior to chemotherapy, then 8 mg orally after six and 12 hours, followed by 8 mg orally eight hourly during days 2-5. Complete control of vomiting occurred in 52 patients (69%) on the first day and 45 patients (60%) on days 2-5. Sixty patients (80%) preferred ondansetron to their previous antiemetics. The efficacy of ondansetron was maintained over multiple chemotherapy cycles. Ondansetron was also given to 16 patients receiving cisplatin chemotherapy. They received 8 mg IV immediately prior to chemotherapy followed by an infusion of 1 mg/hr for 8 hr, with 8 mg orally at the end of the infusion and then 8 mg orally eight hourly during days 2-6. Some control of vomiting (less than = 5 vomits) was achieved in eight patients (50%) on the first day and in 14 patients (87%) on subsequent days. Eight patients (50%) preferred ondansetron to their previous antiemetics. Adverse events with ondansetron were frequent but mild, with constipation and headache being most common. Ondansetron is highly effective in patients refractory to standard antiemetics, especially after noncisplatin chemotherapy.
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PMID:Ondansetron reduces chemotherapy induced nausea and vomiting refractory to standard antiemetics. 153 54

Tropisetron, a 5-HT3 receptor antagonist, was evaluated as antiemetic prophylaxis during postoperative abdominal irradiation of ovarian carcinoma patients. Twenty consecutive women with stages I-III (FIGO) epithelial ovarian carcinomas were included. Nausea, generally mild and of short duration, increased from start (30%) to end of radiotherapy (54%). Episodes of vomiting were few in number and occurred in less than 10% of the cases. Diarrhea was common toward the end of the radiotherapy courses. The overall ratings for quality of life were excellent or good in 75-85% of the cases. Tropisetron seems to be a promising and well-tolerated drug in conjunction with extended radiotherapy.
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PMID:Tropisetron, a new 5-HT3 receptor antagonist, in the prevention of radiation-induced emesis. 154 89

Two new classes of potent 5-HT3 agents have been developed and examined as inhibitors of cytotoxic drug induced emesis in the ferret and dog. The absolute configuration of the most active molecules 10 and 18 have been determined by X-ray crystallography. These two compounds are more potent than known 5-HT3 receptor antagonists both in vivo and in vitro in blocking 5-HT3 receptor activation and preventing chemotherapeutic induced emesis. Compared with 5-HT3 antagonists, such as GR 38032F, zacopride, BRL 43694, and ICS 205-930, compound 10 was more potent in (1) inhibiting binding to 5-HT3 receptor binding sites in rat cortex (Ki = 0.17 nM), (2) blocking the von Bezold-Jarisch effect in the rat (lowest effective dose, 1 microgram/kg iv), and (3) inhibiting 5-HT-induced contraction of guinea pig ileum (lowest effective concentration, 10(-9) M). This novel agent was as effective given po as when given iv in reducing cisplatin-induced emetic episodes in the ferret (ED50 = 4 micrograms/kg iv or po). A 1 mg/kg po dose of 10 virtually abolished cisplatin-induced emesis for 10 h in the ferret. However, it was inactive against apomorphine or copper sulfate-induced vomiting. These data, coupled with receptor binding studies of ligands for D2-dopamine, a1, a2, 5-HT1, 5-HT2, and muscarinic receptors demonstrate that 10 is a highly selective 5-HT3 receptor antagonist with remarkable potency in vivo.
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PMID:Development of high-affinity 5-HT3 receptor antagonists. 2. Two novel tricyclic benzamides. 154 79


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