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)

Several 5-hydroxytryptamine (5-HT3) receptor antagonists have been described. In addition to 5-HT3 receptor antagonist activity, many of these agents also possess gastroprokinetic activity. In the present report, we identify compound LY277359 maleate as a potent, p.o. active, highly selective 5-HT3 receptor antagonist lacking gastroprokinetic effects. LY277359 maleate was a potent and selective antagonist of 2-methyl 5-HT-induced contraction in the guinea pig ileum (KB = 1.6 nM), a response mediated by activation of 5-HT3 receptors. Given both i.v. (0.0003, 0.001 and 0.003 mg/kg) and p.o. (0.01 and 0.03 mg/kg), LY277359 maleate inhibited the bradycardic response to i.v. administered 5-HT in urethane-anesthetized rats. The duration of antagonism of 5-HT-induced bradycardia persisted beyond 6 hr after p.o. administration of LY277359 maleate (0.03 mg/kg p.o.). In contrast to its potent 5-HT3 receptor antagonist activity, LY277359 maleate, in doses up to 1 mg/kg p.o., did not affect gastric emptying in rats, suggesting minimal, if any, gastroprokinetic activity of LY277359 maleate. This is in contrast to another 5-HT3 receptor antagonist, zacopride, which did produce a marked increase in gastric emptying in rats at doses of 0.1 mg/kg p.o. and higher. LY277359 maleate (0.03 and 0.1 mg/kg i.v. and 0.07, 0.1, 0.3 and 1.0 mg/kg p.o.) did have effects consistent with other 5-HT3 antagonists, to inhibit cisplatin-evoked emesis in dogs.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:LY277359 maleate: a potent and selective 5-HT3 receptor antagonist without gastroprokinetic activity. 236 87

The distribution of [3H]zacopride (1.0 nM) to putative 5-HT3 receptor recognition sites in the ferret hindbrain was assessed using autoradiography. Specific binding (defined by the inclusion of granisetron, 1.0 microM) was heterogeneously distributed with highest density within the dorsal vagal complex (area postrema, nucleus tractus solitarius and dorsal motor nucleus of the vagus nerve). Lower densities were detected in the spinal trigeminal nerve complex whilst no other significant specific binding was detected ventral to the dorsal vagal complex. The location of 5-HT3 receptor recognition sites within the dorsal vagal complex may provide sites of action for zacopride and other 5-HT3 receptor antagonists to inhibit the emesis induced by cancer chemotherapeutic agents and x-radiation.
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PMID:Topographical distribution of 5-HT3 receptor recognition sites in the ferret brain stem. 240

The well-documented 5-HT3 receptor antagonists, ICS 205-930 and GR38032F, have been compared with regard to their inhibitory activity at 5-HT3 receptors to another gastrokinetic agent, zacopride. Zacopride and ICS 205-930 showed similar affinity (-log kB approximately 8.0), whereas GR38032F showed lower affinity (-log ka approximately 7.0) at 5-HT3 receptors in the guinea pig ileum. After i.v. administration to anesthetized rats, zacopride was approximately 10-fold more potent than either ICS 205-930 or GR38032F, which were equipotent as inhibitors of serotonin-induced bradycardia (5-HT3-mediated activation of the von Bezold Jarisch reflex). After oral administration to anesthetized rats, zacopride remained approximately 10-fold more potent than ICS 205-903, which was approximately 2-fold more potent than GR38032F as an inhibitor of serotonin-induced bradycardia. Furthermore, the inhibitory effectiveness of GR38032F persisted for less than 3 hr after oral administration and for less than 15 min after intravenous administration. ICS 205-930 produced maximal inhibition of serotonin-induced bradycardia for over 3 hr with heart rate returning to control values 6 hr after oral administration. Zacopride possessed the longest duration of inhibitory effectiveness in urethane-anesthetized rats with maximal inhibition still apparent 6 hr after oral administration. All three agents inhibited cisplatin-induced emesis after i.v. administration in dogs with zacopride being 10-fold more potent than ICS 205-930 or GR38032F, which were equipotent. These comparative data with three 5-HT3 receptor antagonists indicate that in animals, zacopride was more potent and longer acting than either ICS 205-930 or GR38032F. Furthermore, after oral administration to rats, GR38032F was slightly less potent than ICS 205-930 and possessed the shortest duration of action.
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PMID:Comparison of the 5-HT3 receptor antagonist properties of ICS 205-930, GR38032F and zacopride. 252 13

1. The 5-hydroxytryptamine (5-HT3) receptor antagonist, GR 38032F, which possesses potent anti-emetic properties in vomiting induced by cancer chemotherapeutic drugs, has been tested to determine its value in the prophylaxis of motion sickness induced by cross-coupled stimulation. The double-blind trial compared GR 38032F with both a placebo (lactose) and with hyoscine. In addition, studies of ocular pursuit and saccadic eye movements were carried out following the administration of each drug. 2. The prophylactic effect of GR 38032F on motion-induced nausea was indistinguishable from that of placebo, whereas following hyoscine subjects showed a highly significant (P less than 0.001) increase in tolerance to cross-coupled stimulation. Tests of oculomotor function showed no effect on saccadic eye movement from either drug. However, both drugs produced a significant (P less than 0.05) though small reduction in eye velocity gain during pursuit eye movement. 3. These findings suggest that the 5-HT3 receptor is not involved in the neural pathways that bring about motion sickness, but that it may have a role in the control of ocular pursuit. The absence of an anti-motion sickness effect from a drug that is effective in the treatment of vomiting induced by cancer chemotherapy serves to emphasize that different neural mechanisms are involved in the generation of motion sickness.
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PMID:The effect on motion sickness and oculomotor function of GR 38032F, a 5-HT3-receptor antagonist with anti-emetic properties. 252 20

A total of 28 patients receiving cancer chemotherapy with cisplatin-containing regimens (70-120 mg/m2) participated in an evaluation of the efficacy and safety of GR38032F for the prevention of acute nausea and vomiting. GR38032F, a 5HT3 receptor antagonist, was given 30 min prior to cisplatin as an 8-mg loading dose by i.v. infusion over 15 min, followed by continuous infusion at a rate of 1 mg/h for 24 h. Efficacy was assessed by measurement of the number of episodes of retching and vomiting occurring in the 24 h after cisplatin administration and by an assessment of nausea during the same period. In all, 26 patients were evaluable for efficacy: overall, complete control was achieved in 12 patients (46%), major control (1-2 emetic episodes), in 6 (23%); minor control (3-5 episodes), in 1 (4%); control could not be achieved (failure; greater than 5 episodes) in 7 patients (27%). GR3832F was the tolerated, with no significant drug-related adverse events. These encouraging results should be confirmed in comparative trials.
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PMID:GR38032F, a 5HT3 receptor antagonist, in the prophylaxis of acute cisplatin-induced nausea and vomiting. 252 62

The novel 5HT3 receptor antagonist GR38032F was evaluated in the control of emesis induced by the cyclophosphamide analogue ifosfamide. At a dose of 4 mg q 6 h, GR38032F was given to six patients receiving their first dose of ifosfamide infusion (4-6 g/m2 over 24 h); over the 42-h study period, major control of retching and vomiting was achieved in five patients. In the second phase of the study six further patients, in whom high-dose metoclopramide had failed to control emesis, were given 8 mg GR38032F q 6 h; major control of emesis was again observed in five patients. Toxicity attributed to GR38032F was minimal. This selective 5HT3 antagonist is effective and safe in the control of ifosfamide-induced emesis, even in patients resistant to high-dose metoclopramide.
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PMID:The efficacy and safety of GR38032F in the prophylaxis of ifosfamide-induced nausea and vomiting. 252 78

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

Three main types of 5-HT (serotonin) receptor have been recognised. The 5-HT3 receptor is located on neuronal tissues in the peripheral and central nervous systems. Ondansetron is a highly selective and potent antagonist for this receptor type. The severe nausea and vomiting caused by cytotoxic agents and radiotherapy can be reduced by metoclopramide treatment, but extrapyramidal side effects are common due to antagonism of dopamine receptors. Ondansetron has been found to significantly delay the onset of emesis, and reduce the number of retches and vomits in ferrets receiving cisplatin, cyclophosphamide, or radiation, at much lower doses than metoclopramide and without the associated side effects. Experiments to define the site of action of ondansetron suggest that at least part of its antiemetic action is in the area postrema, though a peripheral site of action in the upper gastrointestinal tract is also a possibility.
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PMID:Pharmacological and anti-emetic properties of ondansetron. 253 94

Ondansetron is a 5-HT3 receptor antagonist which has shown activity in the prevention of nausea and vomiting resulting from cytotoxic therapy. This paper describes the results of studies evaluating the efficacy of oral ondansetron in controlling radiation-induced emesis. Initial non-randomised studies showed that doses of 4 mg q.d.s. or 8 mg t.d.s. of ondansetron achieved complete or major control of vomiting in 77-91% of patients and mild or absence of nausea in 72-77% following single exposure high-dose (8-10 Gy) radiotherapy to the upper abdomen. A subsequent double-blind, prospective, randomised trial compared ondansetron 8 mg t.d.s. with metoclopramide 10 mg t.d.s. in the prevention of emesis following single radiation doses of 8-10 Gy to the upper abdomen. On the day of radiotherapy, ondansetron achieved significantly greater control of vomiting and retching (P less than 0.001) and nausea (P = 0.001) than metoclopramide. An advantage for ondansetron was also seen on days 2 and 3 after irradiation, although this did not reach a statistically significant level. Only two patients, out of 154, in all the studies experienced side effects attributable to ondansetron: one developed headache and the other experienced headache and vertigo. These studies show that ondansetron is a safe drug, with activity in the prevention of radiation-induced emesis and significantly greater efficacy than metoclopramide in the control of nausea and vomiting following single exposure upper abdominal high-dose radiotherapy.
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PMID:Clinical studies with ondansetron in the control of radiation-induced emesis. 253 96

As part of an open dose-ranging study, the pharmacokinetics of granisetron (BRL 43694A), a selective 5-HT3 receptor antagonist given by the i.v. route, was studied in 18 patients receiving highly emetogenic cytotoxic drugs, predominantly cisplatin, either alone or in combination with other cytostatic agents. All patients received 30-min infusions of granisetron at a dose of 40 micrograms/kg. Nine showed complete absence of the gastrointestinal side effects normally associated with cisplatin, and in the majority of the remaining patients, the onset and severity of nausea was significantly modified. No acute side effects were observed at this dose and the drug was well tolerated in all cases. Peak plasma concentrations and area under the curve (AUC) values for granisetron showed considerable inter-patient variation. Higher plasma levels of granisetron were observed at 5 h in responding patients compared with those in whom the drug was ineffective in controlling emesis (P less than 0.05). AUC values were higher in responding patients, but this difference was not statistically significant. There was apparently no defined plasma concentration threshold for the drug's anti-emetic effect in these patients. Granisetron seems to be an effective and safe anti-emetic in patients receiving cytotoxic chemotherapy. Further exploration of its dose scheduling and pharmacokinetic profile is warranted.
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PMID:A pharmacokinetic study of granisetron (BRL 43694A), a selective 5-HT3 receptor antagonist: correlation with anti-emetic response. 254 37


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