Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P46098 (5-HT3 receptor)
 2,290 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The emetic potencies of morphine and its metabolite morphine 6-glucuronide have been determined in the ferret by constructing dose-response curves for mean total retches and vomits for subcutaneous doses of 0.05 mg kg-1 to 5 mg kg-1. Morphine 6-glucuronide induced retching and vomiting at lower doses than morphine and at a maximal dose induced more retching and vomiting than morphine. 2. The emesis induced by both morphine and morphine 6-glucuronide was abolished by the preadministration of naloxone (0.5 mg kg-1 s.c.). 3. The 5-HT3 receptor antagonists granisetron and ondansetron (1 mg kg-1, s.c.) failed to abolish or reduce emesis induced by either compound. 4. At a high-dose (5 mg kg-1), morphine but not morphine 6-glucuronide failed to induce emesis and abolished the emesis induced by the cytotoxic drug, cyclophosphamide (200 mg kg-1, i.p.). 5. Preliminary pharmacokinetic studies of intravenous and subcutaneous morphine and morphine 6-glucuronide revealed that morphine 6-glucuronide accounts for less than 1% of the metabolic product of morphine in the ferret. Peak plasma levels of the two compounds after their subcutaneous administration were obtained within 10 min. The metabolic profile of morphine was not dose-dependent. There was no relationship between plasma level and emetic response for either compound.
 ...
PMID:Morphine 6-glucuronide: a metabolite of morphine with greater emetic potency than morphine in the ferret. 132 67

Ondansetron is a highly potent and selective antagonist at 5-HT3 receptors. Its anti-emetic actions were first revealed by its ability to antagonize retching and vomiting induced by chemotherapy and radiotherapy in animals and man. Subsequently, the availability of labelled 5-HT3 receptor ligands allowed identification of 5-HT3 receptors, located at highest densities in the area postrema, nucleus tractus solitarius (NTS), in other areas of the brain, and on afferent terminals of the vagus nerve. Postoperative nausea and vomiting may be caused by various factors: the anaesthetic, associated drugs, the surgical procedure, movement of the patient, sex, weight and pain. These factors mediate their effects via the higher brain circuits, the vestibular nuclei, the chemoreceptor trigger zone in the area postrema, or the upper gastrointestinal tract via the vagus nerve, influencing motor and visceral emetic outputs in the hind-brain. It is hypothesized that ondansetron blocks nausea and vomiting by 5-HT3 receptor antagonism at two specific sites: (i) centrally, in the area postrema/NTS; and (ii) peripherally on vagus nerve terminals. The absence of other pharmacological effects of ondansetron ensures an absence of side-effects.
 ...
PMID:Pharmacology of ondansetron. 142 23

The racemate and (+)- and (-)-isomers of fenfluramine (5 mg kg-1 i.p., 1 h pretreatment) antagonized cisplatin-induced retching and vomiting in the ferret. The intravenous injection of (+/-)-fenfluramine administered on an established cisplatin-induced emesis antagonized the response within minutes of injection. The administration of a lower dose of (+/-)-fenfluramine (1.0 mg kg-1 i.p., 1 h pretreatment) failed to antagonize cisplatin-induced emesis when administered alone but enhanced the antiemetic effects of metoclopramide and ICS 205-930. This pretreatment with (+/-)-fenfluramine failed to enhance the antiemetic effects of zacopride. It is considered that an action of the racemate on presynaptic 5-HT/catecholaminergic systems to reduce neurotransmitter release may enhance the action of certain 5-HT3 receptor antagonists in controlling emesis induced by cisplatin.
 ...
PMID:The actions of fenfluramine and interaction with 5-HT3 receptor-antagonists to inhibit emesis in the ferret. 197 9

The intravenous injection of cisplatin (10 mg/kg), the subcutaneous injection of apomorphine (0.125-1 mg/kg) and lisuride (0.001-0.1 mg/kg), the oral administration of ipecacuanha (0.3-2.4 mg/kg) and the intragastric administration of copper sulphate (25-100 mg/kg), induced a vomiting and retching response in the ferret. Pretreatment with dl-fenfluramine (5 mg/kg i.p.) prevented or reduced the emesis induced by cisplatin, apomorphine, ipecacuanha and lisuride but failed to significantly antagonise copper sulphate-induced emesis. The 5-HT3 receptor antagonist ICS 205-930 (0.1 mg/kg i.p.) prevented emesis induced by cisplatin and ipecacuanha but failed to prevent or significantly reduce the emesis induced by apomorphine, lisuride or copper sulphate. Dopamine receptor antagonists, including fluphenazine (0.1-1.0 mg/kg i.p.) prevented apomorphine- and lisuride-induced emesis but were less potent or had inconsistent actions to antagonise cisplatin- or ipecacuanha-induced emesis and failed to inhibit the emesis induced by copper sulphate. The data indicate that dopamine and/or 5-HT3 receptor systems are involved in drug-induced emesis but that emesis caused by gastric irritation induced by copper sulphate is mediated by different receptor mechanisms.
 ...
PMID:Fluphenazine, ICS 205-930 and dl-fenfluramine differentially antagonise drug-induced emesis in the ferret. 197 49

In a cross-over design of a study of prevention of emesis induced by cancer chemotherapy done in Saitama Cancer Center, the efficacy of oral lorazepam was superior to that of i.v. domperidone. And then, we proceeded a parallel study with use of oral lorazepam and oral domperidone. However, in this situation lorazepam was not superior to domperidone despite accrual of more than 60 patients. Recently, a multi-institutional study has been started in October of 1988 in an evaluation of the efficacy and safety of the new anti-emetic drug of a 5HT3 receptor antagonist, ondansetron. Two methods of its administration were designed. In one study ondansetron was given 2 hr prior to non-platinum chemotherapy as an 2 or 8 mg dose by oral administration, followed by receiving it 6 hr and 12 hr after chemotherapy. In another study, it was given 15 min prior to cisplatin including chemotherapy as an 2 or 8 mg loading dose by i.v. injection over 5 min, followed by continuous infusion at a rate of 0.25 mg/h or 1 mg/h for 24 h, respectively. Efficacy was assessed by measurement of the number of episodes of retching and vomiting occurring in the 24h after administration of chemotherapy and by an assessment of nausea during the same period. This time the major efficacy category was adopted, which is made up of the complete responder and major responder categories of both vomiting and nausea. 19 patients were evaluable for efficacy in the non-platinum group; the major efficacy rates showed 45% in 2 mg-given group and 88% in 8 mg-given group, respectively. 108 patients were evaluable for efficacy in the cisplatin group: the major efficacy rates showed more than 70% in both 2 mg and 8 mg-given group. However, in the patients given more than 75 mg/mg2 of cisplatin, the major efficacy rates were 55% in the 2 mg-given group, compared to 73% in the 8 mg-given group. Ondansetron was well tolerated, with no significant drug-related adverse events.
 ...
PMID:[Gastrointestinal toxicity induced by anticancer drugs--including new antiemetic drugs]. 214 Apr 98

Cancer therapy with cytotoxic drugs such as cisplatin or cyclophosphamide is usually associated with violent crisis of vomiting. Recently, it was shown that 5-HT3 receptor antagonists block cisplatin-induced vomiting but the mechanisms and their sites of action remain unknown. We tested the hypothesis that these agents act on structures within the central nervous system by evaluating the effectiveness of vagal stimulation in eliciting fictive vomiting in decerebrate, paralyzed and ventilated cats before and after administration of such agents. Fictive vomiting was defined as a series of large bursts of synchronous activity in the phrenic and abdominal (expiratory) nerves (retching) followed by a burst in which the abdominal activity was prolonged (expulsion). The latency and number of these co-activations were measured before and after intravenous administration of three 5-HT3 receptor antagonists (GR 38032F (Ondansetron). Zacopride, and BRL 43694A (Granisetron]. All compounds, administered at doses of 1 and 2 mg/kg failed to block vomiting behaviour in 100% and 68% of trials, respectively. Nor did their administration affect the latency and number of co-activations. We conclude that intravenous administration of 5-HT3 receptor antagonists do not act centrally on either the brainstem neuronal network known as the "vomiting center" or related neuronal structures. Our results suggest that the anti-emetic effect of 5-HT3 receptor antagonists in cisplatin-induced vomiting is mediated peripherally rather than centrally.
 ...
PMID:Vagal-induced vomiting in decerebrate cat is not suppressed by specific 5-HT3 receptor antagonists. 229 1

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.
 ...
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.
 ...
PMID:The efficacy and safety of GR38032F in the prophylaxis of ifosfamide-induced nausea and vomiting. 252 78

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.
 ...
PMID:Clinical studies with ondansetron in the control of radiation-induced emesis. 253 96

Recent studies have implicated 5-HT3(5-HT-M) receptors in the genesis of retching and vomiting evoked by antineoplastic agents. Such receptors have so far only been located peripherally, notably on the vagus. Therefore, the effects of bilateral abdominal vagotomy and antagonism of 5-HT3 receptors have been investigated on retching and vomiting induced by radiation. The gastrokinetic substituted benzamide BRL24924, (Beecham Pharmaceuticals) which has 5-HT3 receptor antagonist properties, was used. Using the ferret, it was shown that whole body x-radiation produced retching and vomiting, which was most severe during the 30 min following irradiation, and continued for at least 90 min. Abdominal vagotomy almost totally abolished the retching and vomiting, occurring during the 30 min immediately after irradiation. The following 60 min period was similar to that of control animals. This would suggest that the emetic events can be divided into a vagally-dependent and independent phase. In a small dose, BRL 24924 mimicked abdominal vagtotomy, in a larger dose, it almost totally abolished the retching and vomiting throughout the entire 90 min period. These results suggest that 5-HT3 receptor antagonists are capable of ameliorating radiation-induced retching and vomiting and that, while an important site of their action could be the abdominal vagi, other areas are probably also involved.
 ...
PMID:Evidence for an extra-abdominal site of action for the 5-HT3 receptor antagonist BRL24924 in the inhibition of radiation-evoked emesis in the ferret. 367 May 59


1 2 3 Next >>