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)

Both radiotherapy and chemotherapy for cancer are capable of causing severe nausea and vomiting, which formerly often interfered with the patient's compliance to treatment. The basic pathway and pharmacological mechanisms involved in this are still poorly understood. The recent discovery, however, that 5-HT3 receptor antagonists can prevent or greatly reduce chemotherapy-induced emesis led to a re-evaluation of the sequence of events occurring in the protective emetic reflex, which are reviewed in this paper. The vomiting centre co-ordinates the incoming and outgoing information, and is thought to be represented by complex interactions between different adjacent areas in the brainstem. Whether the main role in the emetic reflex arch is accomplished by either the central part (chemoreceptor trigger zone) or the peripheral part (gastro-intestinal tract) needs further confirmation A more important role, however, of the vagal nerve and the gastro-intestinal tract is generally accepted. The neurotransmitter serotonin (5-HT) appears to play a major role in chemotherapy-induced emesis via the 5-HT receptor. These indications could form the basis for further investigations into the involvement of other neurotransmitters, and the character of their interactions.
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PMID:Pathophysiology of cytotoxic drug-induced emesis: far from crystal-clear. 167

5-Hydroxytryptamine (5-HT) is present throughout the gastrointestinal tract, which acts as the major reservoir of this substance in the body. Its physiologic role has not been clearly established, although it seems likely that 5-HT is involved in the regulation of aspects of intestinal motility such as peristalsis and the migrating motor complex. In disease states the contribution of 5-HT is perhaps more clearly established, particularly its role in chemotherapy-induced emesis, in the carcinoid syndrome, and, possibly, in mediating the effect of some intestinal secretagogues, notably cholera toxin. Many of the functions of 5-HT in the gut have been elucidated as a result of the development of antagonists to 5-HT receptors. However, some of these compounds have 5-HT agonist activity as well as 5-HT receptor blocking activity, making interpretation of their effects in health and disease difficult. Nevertheless, 5-HT receptor antagonists are finding an important place in the management of the carcinoid syndrome and in chemotherapy-induced emesis and may well evolve as important agents for modulating gut motility and for inhibiting secretory states in the small and large intestine. The suggestion that 5-HT3 receptor antagonists might also modulate visceral sensation in the gut is of great interest because of their potential to relieve symptoms of functional bowel disorders such as pain, urgency, and bowel frequency.
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PMID:5-Hydroxytryptamine and 5-hydroxytryptamine-3 receptor antagonists. 177 47

This investigation evaluated the antagonist properties of (-)propranolol, (+)propranolol, metergoline and BMY 7378 on the known effect of 8-OH-DPAT (DPAT) to decrease motion sickness in cats. (-)Propranolol produced a greater decrease in the antiemetic effect of DPAT than did (+)propranolol. Although metergoline produced a decrease in the antiemetic effect of DPAT, the decrease could not be clearly attributed to interactions with 5-HT1A receptors because metergoline alone slightly enhanced motion sickness. Depletion of 5-HT with PCPA produced a weaker, nonsignificant enhancement of motion sickness, while mesulergine had no effect. As neither nonspecific 5-HT receptor blockade with metergoline nor depletion of 5-HT mimicked the antiemetic effect of DPAT, it was concluded that DPAT acts on postsynaptic 5-HT1A receptors to prevent emesis. BMY 7378 alone decreased the incidence of motion sickness. A dose just below this agonist range did not decrease the effects of DPAT.
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PMID:Effects of serotonin antagonists on motion sickness and its suppression by 8-OH-DPAT in cats. 215 Apr 42

The selectivity, peripheral vs. central actions, of the antidopaminergic agent L-646,462 was assessed in two ways. First, elevation of prolactin in serum (peripheral) and homovanillic acid in the striatum were measured in rats. L-646,462 was found to have a central/peripheral activity ratio of 143, whereas comparable values derived for haloperidol, metoclopramide and domperidone were 1.4, 9.4 and 1305, respectively. Second, the ID50 values required to block apomorphine-induced emesis in beagles (peripheral receptor-mediated response) were compared with those required to block apomorphine-induced stereotypy (central receptor-mediated response) in rats. Central/peripheral ID50 ratios of 234, 9.2, 129 and 7040 were obtained, respectively, for L-646,462, haloperidol, metoclopramide and domperidone. The selectivity of L-646,462 for peripheral serotonin (5-HT) receptors in rats was determined by measuring its effectiveness in blocking 5-HT-induced paw edema (peripheral response) and 5-hydroxytryptophan-induced head twitch (central response); a ratio of 114 was obtained. This value agrees nicely with the ratio of 143 derived in the rat ( vide supra) for peripheral selectivity for dopamine receptors. L-646,462 is, therefore, selective in vivo, preferentially blocking dopamine and 5-HT receptors located outside the blood-brain barrier. With regard to dopamine-receptors, L-646,462 was about equipotent and more selective than metoclopramide, while being less potent and less selective than domperidone. Unlike metoclopramide or domperidone, L-646,462 also possessed a reasonably potent 5-HT receptor antagonist effect in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:L-646,462, a cyproheptadine-related antagonist of dopamine and serotonin with selectivity for peripheral systems. 654 78

Intracerebroventricular injection of dopamine (0.5-4.0 mg) produced dose-dependent and short-lasting emesis (1-8 min) in cats, which was abolished after ablation of the area postrema. Relatively selective alpha 2-adrenoceptor antagonists (yohimbine and idazoxan) and a mixed alpha 1- and alpha 2-adrenoceptor antagonist (tolazoline), but not a non-selective alpha 1-adrenoceptor antagonist (prazosin), injected intracerebroventricularly inhibited the emesis induced by intracerebroventricular dopamine. However, dopamine receptor antagonists (chlorpromazine, droperidol, spiperone, domperidone, triflupromazine, sulpiride and metoclopramide), an antimuscarinic drug (atropine), a ganglionic blocking agent (mecamylamine), an opioid receptor antagonist (naloxone) and a 5-HT receptor antagonist (methysergide), all injected intracerebroventricularly, had no significant effect on emesis evoked by intracerebroventricular dopamine. The emetic response to intracerebroventricular dopamine was attenuated in cats pretreated with intracerebroventricular reserpine, 6-hydroxydopamine, alpha-methyl-p-tyrosine and hemicholinium-3. It is postulated that dopamine-induced emesis is mediated through the release of noradrenaline acting at alpha 2-adrenoceptors and that it depends on the integrity of monoaminergic and possibly cholinergic structures within the area postrema. It appears, therefore, that the emetic effect of intracerebroventricular dopamine is mediated by adrenergic rather than dopaminergic mechanisms in the area postrema, at least in the cat.
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PMID:The role of alpha-adrenergic mechanisms within the area postrema in dopamine-induced emesis. 771 46

A wealth of data support a role for serotonin (5-HT) function in the mediation of satiety responses, that are impaired in patients with bulimia nervosa. Testmeal results are presented in which 26 bulimic patients and 17 normal controls were given in randomized, double-blind-fashion, placebo, and the 5-HT agents m-chlorophenylpiperazine (m-CPP, 0.5 mg/kg p.o.) and L-tryptophan (L-TRP, 100 mg/kg i.v.). Three and one-half hours after drug administration, subjects were allowed to eat and lib from a standardized testmeal of 3,500 calories, after which postprandial vomiting was not allowed. M-CPP, but not L-TRP, significantly decreased meal size in the combined group, the controls, and to a lesser extent, the bulimics (P < or = .06). Maximum m-CPP concentrations were inversely correlated to the number of calories consumed in the total group. Following m-CPP, there were significant decreases in carbohydrate, protein, and fat intake in the total group of subjects. There were also trends for decreased carbohydrate and protein intake in the bulimics following m-CPP. There were trends for both m-CPP and L-TRP to reduce fat intake in the controls. Differences in the effects between m-CPP and L-TRP are likely due to differential involvement of 5-HT receptor subtypes at presynaptic and postsynaptic sites. These studies in humans confirm reports in animals that m-CPP decreases food intake, including carbohydrates, protein, and fat in a mixed testmeal.
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PMID:Testmeal responses following m-chlorophenylpiperazine and L-tryptophan in bulimics and controls. 794 45

LY228729 [(-)-4(dipropylamino)-1,3,4,5-tetrahydrobenz-[c,d]indole-6-carboxa mide]], an agonist at the 5-HT1A subtype of 5-HT receptor, was studied as an antiemetic in pigeons dosed with a highly emetic oncolytic agent, cyclophosphamide. An intramuscular injection of 0.32 mg/kg of LY228729 administered 15 min prior to the intravenous injection of 200 mg/kg of cyclophosphamide totally prevented the acute emetic response induced by cyclophosphamide. When used as a rescue therapy in a separate group of pigeons, LY228729 (0.32 mg/kg, i.m.) prevented further emetic episodes when it was administered after vomiting had already been induced by cyclophosphamide. Injections of LY228729 given at intervals over the next 2 d also attenuated the delayed emetic response induced by cyclophosphamide. LY228729 appears to be a broad spectrum antiemetic agent that is effective against the anticipatory, the acute and the delayed stages of emesis induced by oncolytic agents.
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PMID:Effects of a 5-HT1A receptor agonist on acute and delayed cyclophosphamide-induced vomiting. 953 18

Several serotonin (5-HT) receptor subtypes have been defined by pharmacological responses to selective agonists and antagonists and by pathways of receptor-effector coupling. Using molecular techniques, additional receptor subtypes have been described. 5-HT receptors are prevalent in the central nervous system and gut and participate in induction of emesis. 5-HT3 antagonists are used to prevent emesis from cancer chemotherapy and also demonstrate efficacy in radiation-induced nausea, postoperative nausea, hyperemesis gravidarum, and nausea and vomiting with the acquired immunodeficiency syndrome. 5-HT4 agonists exhibit prokinetic properties in nauseated patients with gastroparesis and functional dyspepsia. Conversely, 5-HT4 antagonists have antiemetic activity in some experimental models. The 5-HT1D receptor agonist sumatriptan reduces emesis with migraine headaches and in cyclic vomiting syndrome, most likely via action on central nervous system sites. In other models, 5-HT1A and 5-HT2A/5-HT2C agonists exhibit antiemetic properties. The utility of 5-HT receptor ligands in treating emesis is the subject of active investigation.
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PMID:Serotonin receptor physiology: relation to emesis. 1049 49

In the present study, we investigated the effect of 5-hydroxytryptamine (5-HT) and 5-HT receptor agonists and antagonists on motion sickness in Suncus murinus, and the possibility that the emetic stimulus of 5-HT can alter the sensitivity of the animals to the different emetic stimulus of motion sickness. 5-HT (1.0, 2.0, 4.0 and 8.0 mg/kg ip) induced emesis and that was antagonised by methysergide (1.0 mg/kg ip), the 5-HT(4) receptor antagonist sulphamate[1-[2-[(methylsulphonyl)amino]ethyl]-4-piperidinyl]methyl-5-fluoro-2-methoxy-1H-indole-3-carboxylate (GR125487D; 1.0 mg/kg ip) and granisetron (0.5 mg/kg ip). Pretreatment with 5-HT caused a dose-related attenuation of the emetic response induced by a subsequent motion stimulus, which was not significantly modified by methysergide, granisetron or GR125487D pretreatment. (+)-1-(2,5-Dimethoxy-4-iodophenyl)-2-amino-propane (DOI; 0.5 and 1.0 mg/kg ip), 8-hydroxy-2(di-n-propylamino)tetralin (8-OH-DPAT; 0.1 mg/kg ip) but not methysergide, GR125487D or granisetron, attenuated motion-induced emesis, and that was not affected by pretreatment with ketanserin (2.0 mg/kg, ip) or N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl)cyclohexanecarboxamide trihydrocholoride (WAY-100635; 1.0 mg/kg ip), respectively. Indeed, ketanserin alone (0.1, 0.3, 1.0 and 2.0 mg/kg ip) attenuated motion sickness. These data indicate that 5-HT(1/2), 5-HT(3) and 5-HT(4) receptors are involved in the induction of 5-HT-induced emesis. However, agonist action at the 5-HT(1A/7) and 5-HT(2) receptors, and antagonist action at the 5-HT(2A) receptors can attenuate motion sickness in S. murinus.
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PMID:The effect of serotonin and serotonin receptor antagonists on motion sickness in Suncus murinus. 1221 45

Serotonin (5-hydroxytryptamine) is an ubiquitary monoamine acting as one of the neurotransmitters at synapses of nerve cells. Serotonin acts through several receptor types and subtypes. The profusion of 5-HT receptors should eventually allow a better understanding of the different and complex processes in which serotonin is involved. Its role is expected in the etiology of several diseases, including depression, schizophrenia, anxiety and panic disorders, migraine, hypertension, pulmonary hypertension, eating disorders, vomiting and irritable bowel syndromes. In the past 20 years, seven distinct families of 5-HT receptors have been identified and various subpopulations have been described for several of them. Increasing number of 5-HT receptors has made it difficult to unravel the role of 5-HT receptor subpopulations due to the lack of suitable selective agents. The present review describes the different populations and nomenclature of recently discovered 5-HT receptors and their pharmacological relevance.
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PMID:Serotonin receptors - from molecular biology to clinical applications. 2094 68


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