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)

The radiolabelled opioid receptor binding affinities of morphine and its active metabolite morphine 6-glucuronide at the total mu, mu 1, mu 2 and delta receptors were determined. Morphine 6-glucuronide was found to have a 4-fold lower affinity for the mu 2 receptor (IC50 17 nM and 82 nM for morphine and morphine 6-glucuronide respectively, P = 0.01), the receptor postulated to be responsible for mediating the respiratory depression and gastrointestinal effects after morphine. This provides a possible explanation for the reduced respiratory depression and vomiting seen following morphine 6-glucuronide in man. A similar reduction in affinity of morphine 6-glucuronide was seen at the total mu receptor whilst there was no significant difference seen at the mu 1 or delta receptor. Hence the increased analgesic potency of morphine 6-glucuronide over morphine remains unexplained.
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PMID:Explanation at the opioid receptor level for differing toxicity of morphine and morphine 6-glucuronide. 131 Feb 49

In order to assess the involvement of alpha-1 and alpha-2 adrenoceptors in emesis, the emetic effect of eight alpha agonists was studied in dogs. The i.m. administration of each agonist elicited dose-dependent emesis. The order of potency in inducing emesis was: clonidine greater than oxymetazoline greater than tramazoline greater than naphazoline greater than xylazine greater than epinephrine greater than methoxamine = phenylephrine. The clonidine-induced emesis was antagonized by adrenoceptor antagonists showing alpha-2 blocking activity, yohimbine, tolazoline and phentolamine. Among these antagonists, yohimbine was the most effective. The alpha-1 and beta adrenergic, cholinergic, dopaminergic, histaminergic, serotonergic and opioid receptor antagonists did not prevent the clonidine-induced emesis. The emesis induced by oxymetazoline, tramazoline, xylazine, naphazoline and epinephrine was also antagonized by a selective alpha-2 adrenoceptor antagonist, yohimbine, but not by a selective alpha-1 adrenoceptor antagonist, prazosin. In contrast, methoxamine and phenylephrine-induced emesis was antagonized by prazosin, but not by yohimbine. Neither yohimbine nor prazosin prevented the morphine- and histamine-induced emesis. These results indicate that alpha-2 adrenoceptors are involved in the mediation of emetic action, and that the alpha adrenoceptor-mediated emesis does not involve beta adrenergic, cholinergic, dopaminergic, histaminergic, serotonergic and opioid receptors in the emetic pathway. This study further suggests that alpha adrenoceptors involved in the emesis are mainly of the alpha-2 type, although the involvement of alpha-1 adrenoceptors cannot be ruled out.
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PMID:Alpha adrenoceptor subtypes involved in the emetic action in dogs. 134 47

In the first part of this study, we compared the effects of morphine and trimebutine, two opioid receptor agonists, on small intestinal motility and plasma motilin in dogs. Morphine (100 micrograms/kg iv for 10 min) induced first a typical vomiting myoelectric profile followed subsequently by a migrating electrical activity mimicking phase III of the migrating myoelectric complex; trimebutine (5 mg/kg iv for 10 min) initiated only a migrating phase III-like activity. Despite their different initial contractile effects, both agents induced a significant and similar rise in plasma motilin that preceded the beginning of the premature phase III. In the second portion of the study, naloxone, an opioid receptor antagonist, was infused to verify the influence of endogenous opiates on plasma motilin and on the migrating motor complex. Naloxone (2 mg/kg, then 0.5 mg.kg-1.h-1 iv) delayed significantly the cyclic recurrence of plasma motilin peak increases and of the phase IIIs. In some animals, where naloxone abolished the phase IIIs, the amplitude of the motilin peak increases was significantly diminished. These results suggest 1) that opioid administration increases plasma levels of motilin by a mechanism that is independent of the intestinal contractile activity, and 2) that endogenous opioids could be physiological inducers of plasma motilin increases in the conscious dog.
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PMID:Regulation of plasma motilin by opioids in the dog. 254 42

The gastrointestinal motor correlates of vomiting consist of two contractile events, 1) a giant retrogradely propagated contraction of the upper small intestine, the retrograde giant contraction (RGC) and 2) a series of post-RGC phasic contractions that occur primarily in the lower small intestine. The effects of cholinergic, dopaminergic, serotonergic, and opioid receptor antagonists and an opioid receptor agonist on vomiting and its gastrointestinal motor correlates initiated by apomorphine (APO), CuSO4, or cholecystokinin octapeptide (CCK-8) were determined in awake dogs. Atropine blocked the retrograde giant contraction only, and hexamethonium blocked all jejunoileal motor responses activated by APO, CuSO4, or CCK-8. Domperidone blocked all effects of APO only, whereas haloperidol, methysergide, 1-(1-naphthyl) piperazine, and fentanyl blocked or inhibited responses to both APO and CuSO4. None of the dopaminergic, serotonergic, or opioid receptor antagonists or the opioid receptor agonist affected the gastrointestinal motor responses to CCK-8. Cinanserin or Sch 23390 had no effect on any of the responses activated by APO, CuSO4, or CCK-8. These results suggested that D2 dopaminergic and 5-HT2 serotonergic receptors of the emetic central pattern generator mediate vomiting and its gastrointestinal motor correlates, whereas opioid receptors may mediate tonic inhibition of these responses. In addition, peripheral muscarinic or nicotinic cholinergic receptors but not peripheral 5-HT2, dopaminergic, or opioid receptors mediate the gastrointestinal motor correlates of vomiting.
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PMID:Functional localization of specific receptors mediating gastrointestinal motor correlates of vomiting. 256 2

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

The anti-emetic mechanism of action of fentanyl to inhibit nicotine (5 mg/kg, s.c.)-induced emesis was investigated in Suncus murinus. The anti-emetic action of fentanyl (40 microg/kg, s.c.) was antagonised by the opioid receptor antagonists naltrexone (1 mg/kg, s.c.), naloxone (1 mg/kg, s.c.), M8008 (16S-methylcyprenorphine; 1 mg/kg, s.c.) and MR 2266 (5,9-diethyl-2-(3-furylmethyl)2'-hydroxy-7,7-benzomorphan; 1 mg/kg) but not by naloxone methylbromide (1 mg/kg, s.c.), naloxone methyliodide (1 mg/kg, s.c.), naltrindole (1 mg/kg, s.c.), DIPPA (2-(3,4-dichlorophenyl)-N-methyl-N-[1S)-1-(3-isothiocyanatophenyl)-2-(1- pyrrolidinyl)-ethyl]acetamide; 3 mg/kg, i.p.) or naloxonazine (35 mg/kg, i.p.). This indicates an involvement of mu2-opioid receptors within the brain to mediate the anti-emetic effect of fentanyl. In other studies, naloxone 10-60 mg/kg, s.c. induced dose-related emesis but naltrexone was only emetic at 60 mg/kg, s.c. and naloxone methylbromide failed to induce emesis at doses up to 60 mg/kg, s.c. The emesis induced by a high dose of naloxone 60 mg/kg, s.c. was antagonized by CP-99,994 ((+)-(2S,3S)-3-(2-methoxybenzylamino)-2-phenylpiperidine; 3-30 mg/kg, i.p.), 8-OH-DPAT, ((+/-)-8-hydroxy-dipropylaminotetralin; 0.003-0.3 mg/kg, s.c.), buspirone (3 mg/kg, s.c.) and fluphenazine (1-3 mg/kg, i.p.) but not by naltrexone (1-30 mg/kg, s.c.), metoclopramide (0.3-3 mg/kg, i.p.), sulpiride (0.3-3 mg/kg, i.p.), domperidone (0.1-3 mg/kg, i.p.), ondansetron (0.3-3 mg/kg, i.p.), granisetron (0.3-3 mg/kg, i.p.), scopolamine (0.3-3 mg/kg, i.p.) or promethazine (0.3-3 mg/kg, i.p.). The data is discussed in relation to opioid receptor mechanisms moderating emesis and the identification of potential sites of drug action available to inhibit the emetic reflex.
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PMID:Modulation of emesis by fentanyl and opioid receptor antagonists in Suncus murinus (house musk shrew). 1042 43

As has been demonstrated in binding studies the two opioids tilidine (CAS 27107-79-7)/naloxone (CAS 357-08-4) and tramadol (CAS 36282-47-0) differ in regard to their affinities to the opioid receptor site. Therefore it is of interest to evaluate whether such a difference in opioid affinity is also seen in the pharmacological effects of clinically relevant doses in man. Following institutional approval by the local ethical committee and informed consent, 12 volunteers received oral doses of tramadol (100 mg), tilidine/naloxone (100 mg) and placebo, respectively, in a randomized, double-blind cross-over design. In order to determine the degree of constipation, oral-caecal transit time was measured using the H2-exhalation test. Additionally, in order to evaluate a centrally mediated effect, the response of the pupil to light was quantified using the pupillary light reflex technique. Both, peripheral and central mediated effects were compared to placebo. Tramadol as well as tilidine/naloxone induced a significant (p < 0.05) prolongation of oral-caecal transit when compared to placebo. However, prolongation of oral-caecal transit was significantly longer in the tilidine/naloxone (p < 0.05) than in the tramadol group. Compared to tramadol, the pronounced constipating effect of tilidine/naloxone is likely to be due to the 10 fold higher affinity of that drug to the peripheral opioid receptor sites in the intestinal tract, which are responsible for normal propulsion. Such difference in binding is underlined by a central effect, the pupillary light reflex response. The amount of constriction of the iris to light was reduced after both opioids. Again, tilidine/naloxone significantly reduced (p < 0.001) the pupillary light reflex when compared to tramadol. Other side effects such as tiredness, nausea, emesis and dry mouth were more often reported after tilidine/naloxone than after tramadol (40% versus 15%; p < 0.05). Vertigo and perspiration were more often reported after tramadol than after after tilidine/naloxone (58% and 78% versus 8%; p < 0.01). All these data support the findings that while tramadol is considered an opioid, it does not mediate its main clinical relevant properties via binding at the opioid receptor. More likely, due to its monoaminergic reuptake mechanism, to a lesser extent opioid-like effects are induced.
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PMID:Effects of tramadol and tilidine/naloxone on oral-caecal transit and pupillary light reflex. 1068 12

It is well accepted that long-term administration of opioids results in a dose-related constipation. No data so far have demonstrated conclusively whether such constipation is also seen after intake of a controlled release formulation. It was therefore of interest to evaluate whether increasing doses of a controlled release formulation of dihydrocodeine (DHC, CAS 125-28-0) after oral administration also induces a dose-related increase in constipation. Additionally, it was of interest to study whether such a peripheral opioid-related side effect is also seen in another, central receptor-mediated effect, the constriction of the pupil, at clinically relevant doses. Twelve volunteers were given controlled release DHC (60 and 120 mg, respectively) or placebo orally within a randomized, double-blind cross-over study. In order to determine the degree of constipation, oro-cecal transit time was measured using the H2-exhalation test. Additionally, in order to evaluate a centrally mediated effect, the response of the pupil to light was quantified using the pupillary light reflex technique. Both, peripherally and centrally mediated effects were compared to placebo. DHC at both dosages induced a significant (p < 0.01) prolongation of oro-cecal transit time when compared to placebo. However, prolongation of oro-cecal transit was not significantly longer when comparing the lower (60 mg) with the higher dose (120 mg). DHC also induced a significant (p < 0.005) depression of the pupillary light reflex from 53.9 mm (control) to 8.3 and 7.4 mm, respectively. Similar to intestinal transit, the pupillary light reflex was not significantly different among the two doses of DHC. Also, both dosages induced a similar amount of side effects. Tiredness and dry mouth were reported in 80% after both doses while vertigo was reported in 5% and 1% complained of headache. None of the volunteers reported nausea or emesis. It is concluded that opioid receptor sites, which are located in the plexus myentericus of the intestinal wall, are responsible for the delay in propulsion. Because of the controlled release of a fixed amount of DHC over time there is constant binding of the ligand followed by a constant conformational change of peripheral and central receptor sites. Thus constant release induces no dose-related increase in oro-cecal transit and inhibition of the pupillary light reflex.
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PMID:Dose-related effects of controlled release dihydrocodeine on oro-cecal transit and pupillary light reflex. A study in human volunteers. 1121 27

The aim of the present study was to investigate an opioid receptor involvement in the adaptation response to motion sickness in Suncus murinus. Different groups of animals were treated intraperitoneally with either saline, morphine (0.1 and 1.0 mg/kg), naloxone (1.0, 10.0 and 5.0 mg/kg) or a combination of naloxone plus morphine in the absence or 30 min prior to a horizontal motion stimulus of 1 Hz and 40 mm amplitude. For the study of adaptation, different groups received saline on the first trial, and in subsequent trials (every 2 days) they received either saline, naloxone (1.0 and 10.0 mg/kg, i.p.) or morphine (0.1 mg/kg, i.p.) 30 min prior to the motion stimulus. Pretreatment with morphine caused a dose-related reduction in emesis induced by a single challenge to a motion stimulus. Pretreatment with naloxone alone did not induce emesis in its own right nor did it modify emesis induced by a single challenge to a motion stimulus. However, pretreatment with naloxone (5.0 mg/kg, i.p.) revealed an emetic response to morphine (P<.001) (1.0 mg/kg, i.p.) and antagonised the reduction of motion sickness induced by morphine. In animals that received saline or naloxone (1.0 mg/kg), a motion stimulus inducing emesis decreased the responsiveness of animals to a second and subsequent motion stimulus challenge when applied every 2 days for 11 trials. However, the animals receiving naloxone 10.0 mg/kg prior to the second and subsequent challenges showed no significant reduction in the intensity of emesis compared to the first trial. The data are revealing of an emetic potential of morphine when administered in the presence of a naloxone pretreatment. The administration of naloxone is also revealing of an additional inhibitory opioid system whose activation by endogenous opioid(s) may play a role in the adaptation to motion sickness on repeated challenge in S. murinus.
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PMID:Opioid receptor involvement in the adaptation to motion sickness in Suncus murinus. 1152 74

The three-step analgesic ladder, originally proposed for cancer pain relief by the World Health Organization (WHO), is now widely employed for all types of pain, including the chronic pain of musculoskeletal disease. Tramadol, an analgesic with weak opioid receptor affinity and possessing monoaminergic activity, has proved suitable for use at Step 2 of the WHO ladder. Owing to its pharmacological properties, tramadol is more appropriate than NSAIDs for patients suffering from gastrointestinal and renal problems. Importantly, the analgesic potency of tramadol is greater than that of NSAIDs and of other weak opioids (codeine, dextropropoxyphene). It also causes fewer opioid-type adverse effects, e.g. nausea, drowsiness, vomiting, dry mouth and constipation. In chronic musculoskeletal pain it is recommended that tramadol should be given by mouth and by the clock; the initial dose should be titrated upward gradually to reach the individual level required for suitable pain control. This dosage strategy will also minimise the usual opioid-type adverse effects encountered with tramadol. Four recent publications are reviewed to illustrate the efficacy of tramadol, alone or in conjunction with an NSAID, in the management of low back pain, osteoarthritis pain and breakthrough pain.
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PMID:Tramadol in musculoskeletal pain--a survey. 1195 1


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