Disease relevance of Meptazinol

• Meptazinol diminishes the Jarisch-Herxheimer reaction of relapsing fever [1].
• The oral use of meptazinol in patients with chronic liver disease is associated more with the development of nausea and vomiting rather than excessive sedation [2].
• Enhanced oral bioavailability of meptazinol in cirrhosis [2].
• Intramuscular meptazinol and morphine in postoperative pain [3].
• In the therapeutic dose range, meptazinol produced miosis, morphine-like identification and symptoms, limited liking, and some dysphoria [4].

Psychiatry related information on Meptazinol

• A dose-ranging study of meptazinol was carried out using the pain threshold to electrical tooth pulp stimulation in healthy volunteers as the pain model [5].
• Meptazinol (100 mg) increased the component of mood assessments related to wakefulness (p less than 0.05) [6].

High impact information on Meptazinol

• Meptazinol, 140 and 280 mg, decreased body temperature [4].
• In studies in patients with moderate to severe pain of various aetiologies, usually following surgery or in obstetrics, the characteristics of analgesia with meptazinol were comparable to those seen with equianalgesic doses of pentazocine, pethidine or a combination of dextropropoxyphene and paracetamol [7].
• It is suggested that prevention of physostigmine-induced lethality by meptazinol is a consequence of its protective action on AChE in the central nervous system [8].
• Meptazinol has a similar agonist action on opioid receptors in field-stimulated mouse vas deferens and guinea-pig ileum [9].
• Meptazinol and levorphanol hyperphagia was abolished by 1 mg kg-1 doses (i.p.) of the opioid antagonists naltrexone, naloxonazine and (-)-Mr 1452 but not by its (+)-enantiomer Mr 1453 which is not effective as an opioid antagonist [10].

Chemical compound and disease context of Meptazinol

• Restoration of mean arterial pressure in endotoxic shock by meptazinol. Contributions from lysosomal membrane stabilisation, opiate antagonism and noradrenaline release [11].
• The respiratory depression induced by meptazinol, but not that induced by morphine, was enhanced by pretreatment with atropine [12].
• Pethidine 1 mg kg-1 produced respiratory depression which was greater than that produced by meptazinol 1 mg kg-1 [13].
• Carbon dioxide retention and other compensatory mechanisms attenuate the ventilatory depression of meptazinol, but these may be inadequate in the anaesthetized patient [14].
• Double-blind parallel study of meptazinol versus diflunisal in the treatment of lumbago [15].

Biological context of Meptazinol

• 3 In antiarrhythmic doses, meptazinol had little effect on either heart rate or systemic arterial blood pressure [16].
• An intravenous infusion of either meptazinol or naloxone (cumulative 2 mg kg-1, i.v.) partially restored blood pressure [17].
• The influence of gastric emptying on plasma concentrations of the analgesic, meptazinol [18].
• The individual (+)- and (-)-enantiomers of meptazinol (2 mg kg-1 i.p.) induced comparable increases in cumulative food intake [10].
• Both additional competition studies and saturation studies indicate that the meptazinol-sensitive binding of the 3H-ligands corresponds to the high affinity, or mu-1, binding site [19].

Anatomical context of Meptazinol

• When superfused with meptazinol in vitro normal rat papillary muscle stimulated at 1 or 3 Hz showed an increase in APD90 and a decrease in dV/dtmax [16].
• 2 In similar doses, pretreatment with meptazinol also reduced ventricular arrhythmias, including fibrillation, in conscious rats subjected to coronary artery occlusion [16].
• In addition meptazinol slightly reduced skeletal muscle flow [17].
• 5 The antiarrhythmic effect of meptazinol in these models can probably be explained by direct actions on the cardiac muscle action potential (increase in APD) although effects on opiate receptors cannot be ruled out [16].
• The effect of meptazinol in the spinal cord on carrageenan-induced hyperalgesia was investigated [20].

Associations of Meptazinol with other chemical compounds

• Pethidine compared with meptazinol during labour. A prospective randomised double-blind study in 1100 patients [21].
• These observations suggested that mu opioid receptor rather than muscarinic acetylcholine receptor may be involved in the anti-hyperalgesia of meptazinol in the spinal cord [20].
• Using a computerized autoradiographic subtraction technique, we have examined the regional distribution of meptazinol-sensitive [3H][D-Ala2,MePhe4,Gly(ol)5]enkephalin (DAGO) binding and compared this with the distribution of mu 1 binding determined by competition with low [D-Ala2,D-Leu5]enkephalin (DADL) concentrations [22].
• Tail flick latency elevations induced by meptazinol, a putative mu-1 receptor agonist, were also attenuated by CCK-8-S according to a U-shaped dose-response relationship, but those induced by U-50,488, a kappa agonist, were not antagonized by CCK-8-S doses that attenuated morphine analgesia [23].
• In a double-blind investigation of the efficacy on pain following abdominal or orthopaedic surgery, meptazinol 100 mg, a new hexahydroazepine derivative, was found to be equipotent with pentazocine 60 mg and pethidine 100 mg when given i.m. Analgesia was maximal 30-60 min after injection and was still present at the end of 2 h [24].

Gene context of Meptazinol

• The phenylazepine meptazinol, the pyrrolo-[2,3-b]-indole derivative eseroline and the benzomorphan normetazocine were the most potent inhibitors of AChE among the compounds tested [25].
• The opioids which inhibited horse serum BuChE were in order of potency: meptazinol, methadone, profadol, levallorphan and 1,2,3-trimethyl-3-(3-hydroxyphenyl)-piperidine [25].
• It was concluded that the augmented AVP release following meptazinol administration was likely to be a non-specific response induced by nausea and not an effect mediated by opiate receptors [26].
• Meptazinol and pentazocine: effects on prolactin, growth hormone and vasopressin levels in plasma [26].
• Meptazinol: a novel Mu-1 selective opioid analgesic [19].

Analytical, diagnostic and therapeutic context of Meptazinol

• Meptazinol was assessed in nine opioid abusers according to a double-blind, randomized, crossover design to determine if it produced typical morphine effects [4].
• Valid relative potency estimates of morphine to meptazinol were obtained for self-reported liking, opiate symptoms, and pupillary constriction [4].
• Respiratory depression has only been observed in patients receiving meptazinol as a premedication or while undergoing anaesthesia [7].
• In experimental animal models of haemorrhagic shock, meptazinol has a similar cardiovascular profile to naloxone [17].
• The postoperative hormonal response to surgical stress was measured in 20 patients undergoing hysterectomy who were given either meptazinol 100 mg or morphine 15 mg intramuscularly at the end of the surgery [27].

References