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PubMedDate not supplied

Inhibition by opiate narcotics of rat flexor alpha-motoneurones.

Specific effects of opiate narcotics on rat flexor alpha-motoneurones were studied in ventral roots of laminectomized rats under halothane anaesthesia. The alpha-motoneurones were activated by tetanic stimulation of the cut ipsilateral common peroneal nerve, exciting up to group II- but not group III- and C-afferents. Morphine (0.5--3.0 mg/kg i.v.) reduced or completely suppressed the discharge rate of flexor alpha-motoneurones in a dose-dependent manner. This effect was antagonized by naloxone (0.5 mg/kg i.v.) and mimicked by levorphanol (1.0 mg/kg i.v.), but not by an equal dose of its stereoisomer dextrorphan, suggesting that the effect described is a specific one. After spinalization, the inhibitory effect of morphine was abolished. Previous studies had shown that opiates (e.g. morphine, given in a dose of 2 or 4 mg/kg i.v.) excite rat extensor alpha-motoneurones, an effect opposite to the opiate narcotic action on flexor alpha-motoneurones. The action of opiates leading to an inhibition of flexor alpha-motoneurones may contribute to akinesia and catalepsy, and opioid-induced muscular rigidity. From the results presented it appears that morphine produces a reciprocal change in the activity evoked in extensor and flexor reflex pathways.

Animals↗
PubMed1998

[Economic evaluation in a trial of medically controlled prescription of narcotics to dependent users (PROVE)].

In the 1994-1996 trial of medically controlled prescription of narcotics to dependent users, 800 places were ascribed to heroin substitutes and another 200 for methadone and morphine substitutes. The trial was evaluated with the aid of an accompanying research. Among the results demonstrated in the evaluation was an improvement of the health of the participants. The economic assessment was drawn from observations of health effects within a sub-sample of 142 participants from four centers. In a retrospective statistical survey, for each acute illness which could be influenced through the trial, the number of diagnoses was recorded in the first and thirteenth month after study entry. Also, based on a number of representative cases for each of these acute illnesses, the resource use, i.e. the types and numbers of medical products and services rendered to the patients, was recorded. The results showed a clear decline in depressive episodes, skin diseases, digestive system disorders as well as epileptic attacks and intoxication. Treatment costs could be reduced from a total of CHF 94875.--to CHF 21,998.--/month or from CHF 22.27 to CHF 5.15/patient per day. The improvement of somatic and psychic health due to the medically controlled prescription of narcotics resulted in a benefit of CHF 17.11/person per day.

Depression↗
PubMed1982

Failure of narcotic antagonist to alter electroacupuncture modification of halothane anaesthesia in the dog.

Sixteen dogs were used to study the analgesic effects of electroacupuncture. Electroacupuncture lowered halothane MAC significantly (1.21 +/- 0.04 to 1.05 +/- 0.05 per cent, p less than 0.005). Reversibility of this effect by narcotic antagonist was then studied, using naltrexone 5 mg . kg-1 injected intravenously (10 dogs) or 0.5 mg . kg-1 intrathecally (3 dogs). We failed to see any reversal of the effect of electroacupuncture on MAC. Narcotic antagonist reversibility of acupuncture effect is taken currently to imply endorphin mediation. Possible explanation for our result include an electroacupuncture analgesia not mediated by endorphins.

Acupuncture Therapy↗
PubMed2006

The efficacy of autologous platelet gel in pain control and blood loss in total knee arthroplasty. An analysis of the haemoglobin, narcotic requirement and range of motion.

Biological materials used to assist in haemostasis following total knee arthroplasty have been the subject of much recent research. Autologous platelet gel is a substance that is derived from platelet-rich plasma extracted from the patient's blood and centrifuged perioperatively, and is applied to exposed tissues, synovium and the lining of the wound at closure. Concentrating and applying these factors directly to the wound at the end of a total knee arthroplasty procedure may lead to more complete haemostasis, a reduction in perioperative blood loss, accelerated tissue repair and decreased postoperative pain. In this study, 98 unilateral total knee arthroplasties were evaluated retrospectively, 61 of which involved the intaroperative use of platelet gel, and 37 of which served as control subjects. Outcomes analysed were postoperative haemoglobin changes, intravenous and oral narcotic requirements, range of motion on discharge and total days in hospital. Patients receiving platelet gel during surgery had less postoperative blood loss as measured by differences in the preoperative and postoperative haemoglobin on day 3 (2.7 vs. 3.2 g/dl; P=0.026). The narcotic requirement was less in the platelet gel group for both intravenous (17.0 vs. 36.3 mg/day; P=0.024) and oral (1.84 vs. 2.75 tabs/day; P=0.063) medication. This group also achieved a higher range of motion prior to discharge (78.2 vs. 71.9; P=0.052) and were discharged an average of 1 day earlier than their control counterparts. Though further prospective trials are necessary, this study indicates that the application of autologous platelet gel may lead to improved haemostasis, better pain control and a shortened hospital stay.

Administration, Topical↗
PubMed1982

Antagonism of gut, but not central effects of morphine with quaternary narcotic antagonists.

Naltrexone methylbromide and naloxone methylbromide, quaternary derivatives of naltrexone and naloxone respectively, are assumed to act peripherally. Both compounds reversed the intestinal stimulating effect of morphine in the dog. Naltrexone methylbromide 5 mg/kg s.c. blocked morphine-induced intestinal spike potentials for 50 min while intravenous doses caused antagonism for only 25 min. The antagonism by the s.c. route approximated that produced by naltrexone 0.2 mg/kg s.c. In morphine-dependent dogs, naltrexone methylbromide did not appear to antagonize morphine centrally in doses ranging from 0.25 to 50 mg/kg s.c. since it did not induce behavioral signs of narcotic withdrawal. Similarly, i.v. naloxone methylbromide was also able to reverse morphine-induced intestinal spike potential in dogs but the protection lasted only 25 min. In rats, naltrexone methylbromide 10 and 30 mg/kg i.p. neither reversed morphine block of PGF2 alpha-induced diarrhea nor antinociception. This suggests a lack of CNS narcotic antagonism in both test. In mice, naltrexone methylbromide, 60-720 mg/kg orally and 3-140 mg/kg i.p. failed to block morphine inhibition of prostaglandin F2 alpha-induced diarrhea. Paradoxically, in this species, 30 mg/kg s.c. of naltrexone methylbromide appeared to cross the blood-brain barrier since this dose reversed morphine-induced antinociception. In conclusion, naltrexone methylbromide effectively antagonizes the acute gut stimulating effect, but not the chronic behavioral effect of morphine administration in dogs. Based upon the antinociception test, naltrexone methylbromide does not cross the blood-brain barrier in rats but may in mice. Morphine inhibits prostaglandin F2 alpha-induced diarrhea by a central mechanism in rodents.

Animals↗
PubMed1985

The use of quaternary narcotic antagonists in opiate research.

Quaternary ammonium derivatives of narcotic antagonists are commonly used in determining sites of action of opiates in the central nervous system and the periphery because it is widely assumed that they do not readily cross the blood-brain barrier, in contrast to their relatively non-polar tertiary counterparts. However, these compounds possess several unique pharmacological properties which have not been taken into consideration in the design of numerous investigations. This article reviews the current state of knowledge concerning the pharmacology of the quaternary narcotic antagonists, examines their use in physiological and behavioral studies of action of opiates, and proposes guidelines for the design of experiments involving these compounds.

Animals↗
PubMed1986

Sensitivity to the narcotic cue in non-dependent, morphine-dependent and post-dependent rats.

Using a food-reinforced two-lever operant procedure, 12 rats were trained to discriminate 10 mg/kg (i.p.) of morphine from saline. Five animals were given daily non-contingent exposure to morphine (20 mg/kg on saline, or no-test days, and 10 mg/kg on drug days) from the beginning of the experiment; the others received injections of saline. In the morphine generalization tests, the dependent rats showed an increased sensitivity to the narcotic cue as compared with non-dependent animals (ratio of the ED50 values: 2.30). This increased sensitivity was still present 3 months after discontinuing the non-contingent treatment with morphine (ratio of the ED50 values: 1.98). The results of the present study, together with other results reported in the literature, suggest that the experimental procedure plays a role in determining whether tolerance, no tolerance or enhanced sensitivity to the discriminative stimulus properties of narcotics, is observed.

Animals↗
PubMed1981

A simple, reliable method for predicting the physical dependence liability of narcotic antagonist analgesics in the rat.

The rat intraperitoneal infusion procedure was used to chronically administer drugs for evaluation of the physical dependence liability of narcotic antagonist analgesics. Three methods were used to assess dependence liability: presence of withdrawal signs upon abrupt cessation of chronic infusion (primary dependence), attenuation of the withdrawal signs produced by cessation of chronic morphine infusion (morphine substitution), and production of withdrawal signs when chronically morphine-fused rats were administered the drugs (precipitated withdrawal). Butorphanol, nalbuphine and pentazocine all caused a mild withdrawal in the rat primary dependence model which agrees with the conclusions from experiments with monkey and man. None of these agents substituted for morphine in the rat and three appeared to precipitate withdrawal. Two experimental drugs, Codorphone and TR5400, did not induce primary dependence in the rat, and in chroni-morphinized rats, they precipitated a withdrawal syndrome comparable to naloxone. Another experimental drug, TR5257, substituted for morphine. The correlation between these observations in the rat and previously published data from the monkey are excellent. It is proposed that the rat could be used as a reliable indicator of potential physical dependence liability for the narcotic antagonist analgesics.

Analgesics, Opioid↗
PubMed1981

Behavioral effects of phenylpiperidine narcotic antagonists.

The effects of three phenylpiperidines were studied in pigeons responding under a multiple fixed-ratio 30-response, fixed-interval 5-minute schedule of grain presentation. The first one studied was LY-27372 which as narcotic agonist analgesic effects but not antagonist activity. It decreased responding in both components and was not antagonized by naloxone. The two other drugs, LY-88329 and LY-99335, are tri-alkyl-4-phenylpiperidines which have narcotic antagonist activity. They decreased responding at doses of 5 and 40 mg/kg, respectively, when administered alone. When administered in combination with 20 mg/kg of morphine, they antagonized morphine's effects at 0.16 and 0.08 mg/kg respectively. A 10 mg/kg dose of pentobarbital attenuated the behavioral suppressant effects of 40 mg/kg of LY-99335, but not the suppressant effects of 5 mg/kg of LY-88329 or of 10 mg/kg of LY-27372. The data show that LY-99335 has a large separation between the doses which antagonized morphine and those which alone produce behavioral suppression by a proconvulsant effect at higher doses.

Animals↗
PubMed1981

The effect of neuroleptics, tranquillizers, narcotics, antidepressants and anticonvulsive drugs on the alterations of mouse behaviour caused by acetaldehyde.

In a study of the effect of 26 psychoactive drugs on the complex of mouse behaviour changes caused by acetaldehyde it was found that tranquillizers, hypnotics, sodium oxybutyrate and ethanol are the most efficient. The differences in teh drug effects were determined by a tan alpha criterion. Antidepressants and neuroleptics have equal tan alpha, whereas narcotics, anti-convulsive drugs and tranquillizers all have similar tan alpha, but greater than that of the antidepressants and neuroleptics. A direct dose/effect relationship was found to exist for all the drugs investigated except for neuroleptics and antidepressants. For the latter drugs an increase in dose is followed by an increased effect, which, however, decreases on further increase of the dose. The convulsive syndrome is completely abolished only by tranquillizers and narcotics. Our results are quite in agreement with clinical data about the effectiveness of psychoactive drugs in the treatment of the alcohol abstinence syndrome. The method can be used not only for screening purposes, but also to define the specificity in the action of antialcoholic drugs.

Acetaldehyde↗
PubMed1986

Publication trends in fetal alcohol, tobacco and narcotic effects.

The rate of increase in publications dealing with pregnancy and three types of drugs--alcohol, tobacco and narcotics--was compared for the years 1973-1983 using Medline as literature source. The absolute number of publications for each of the three drug types per year was obtained and was used to calculate the percentage of articles for that type. The absolute number of articles on alcohol and on alcohol and pregnancy increased faster than the comparable absolute rates for the other two. The percentage of articles on pregnancy and alcohol, relative to all articles on alcohol, increased at a faster rate than that for narcotics, but not for tobacco articles.

Ethanol↗
PubMed1981

Transcultural use of narcotic water lilies in ancient Egyptian and Maya drug ritual.

Comparisons are made between ancient ritual uses of the flowers of Nymphaea (Nymphaeaceae) in Maya and Egyptian civilizations. Recurrent motifs encountered in the art of both of these ancient civilizations suggests that the role fo the water lily was that of a narcotic (psychodysleptic) used to mediate ecstasis among a priestly caste. Relevant literature is reviewed as are chemical data. Elements in the complex belief systems of these two civilizations need to be reinterpreted in view of the use of two water lilies as ritual narcotics. The species implicated are Nymphaea caerulea Sav., in Egypt, and N. ampla DC., among the Maya.

Animals↗
PubMed1983

William Osler: narcotic-induced pulmonary edema.

William Osler described the first reported case of narcotic-induced pulmonary edema in 1880. The description is that of autopsy findings of a patient who died of narcotic poisoning. Since that time, noncardiogenic pulmonary edema has come to be known to accompany overdose with a number of drugs, most notably heroin. Clinical manifestations and radiographic findings vary. The exact pathogenesis is unclear, although the mechanism is known to involve increased alveolar capillary permeability. Treatment consists of reversal of respiratory depression, oxygenation, and respiratory support. Rapid improvement with treatment is the rule.

Adult↗
PubMed2003

Pharmacokinetics of high doses of intramuscular and oral heroin in narcotic addicts.

BACKGROUND: In several countries medical prescription of diacetylmorphine is currently being evaluated as a treatment option for heavily dependent narcotic addicts. Because of damaged veins, many patients administer diacetylmorphine intramuscularly or orally. Therefore we characterized the pharmacokinetics of intramuscular and oral diacetylmorphine in the high dose range usually required in narcotic addicts. METHODS: Three intramuscular doses, 3 oral doses, and 1 intravenous dose of diacetylmorphine and oral and intravenous test doses of deuterium-labeled morphine (morphine-N-methyl-d3 [morphine-d3]) were administered to 8 heroin-addicted patients. Arterial plasma concentrations of diacetylmorphine, monoacetylmorphine, morphine, morphine-3-glucuronide, morphine-6-glucuronide, and morphine-d3 were measured by liquid chromatography-mass spectrometry. RESULTS: Intramuscularly administered diacetylmorphine (</=200-250 mg) exhibited linear diacetylmorphine, monoacetylmorphine, and morphine kinetics and resulted in sustained diacetylmorphine exposures (bioavailability, 380% +/- 157% [mean +/- SD]) and in lower and delayed peak monoacetylmorphine and morphine concentrations as compared with intravenous administration. Oral diacetylmorphine (</=600 mg) yielded negligible systemic diacetylmorphine and monoacetylmorphine exposures but was associated with linear kinetics and high bioavailabilities for morphine (67% +/- 19%), morphine-3-glucuronide (205% +/- 52%), and morphine-6-glucuronide (180% +/- 61%). In addition, oral diacetylmorphine was absorbed more rapidly and to a greater extent than a concomitant test dose of morphine-d3. CONCLUSIONS: On the basis of the linear pharmacokinetics, the high bioavailability of intramuscular diacetylmorphine, and the rapid and extended morphine absorption from oral diacetylmorphine, the intramuscular and oral routes can be recommended as safe and feasible alternatives to the intravenous route for medical prescription of diacetylmorphine.

Administration, Oral↗
PubMed1996

Stimulants, narcotics and beta-blockers: 25 years of development in analytical techniques for doping control.

More than 25 years of developing doping control methods have led to comprehensive screening and confirmation procedures for stimulants, narcotics and beta-blockers. Much of this work has been initiated and/or improved by the late Prof. Dr. Manfred Donike. The methodological approach covered in this overview was applied to doping control procedures during the XXV Summer Olympics in Barcelona, Spain, in 1992 and the XVII Winter Olympics in Lillehammer, Norway, in 1994. Urine samples are screened through a combination of two analytical methods that are complementary: (a) gas chromatographic analysis of the parent compound and unconjugated metabolites, following single-step sample extraction and detection by a nitrogen-specific detector based on a retention index identification system and (b) gas chromatographic analysis including also conjugated drugs and metabolites after hydrolysis, solid-phase extraction, derivatisation and mass spectrometric detection. Confirmation and identification is always performed by gas chromatographic separation and full scan mass spectrometric detection. These methods facilitate the rapid screening and confirmation of more than 100 stimulants, narcotic analgesics and beta-blockers in urine for at least 24 h after the intake of a pharmaceutical dose. Application of the methods ensures high quality standards for the unequivocal identification of doping agents as well as a rapid turnaround time for sample analyses.

Adrenergic beta-Antagonists↗
PubMed1980

Analgesic narcotic antagonists. 2. 8-Alkymorphinan-6-ones.

A series of 8-alkyl-3-methoxy-17-methylmorphinan-6-ones (3C) and -isomorphinan-6-ones (3T) were prepared by conjugate addition of lithium dialkylcuprates to the corresponding 7,8-didehydro-6-ones 2C and 2T. These 17-methyl compounds were potent analgesics and were converted to mixed narcotic agonists-antagonists 7-10, by replacement of the 17-methyl groups with cycloalkylmethyl moieties. The 8 substituent modified the type of activity observed. One of these compounds, 17-(cyclobutylmethyl)-3-hydroxy-8 beta-methylmorphinan-6-one (10Ca), had an agonist-antagonist ratio of 0.1. Compound 10Ca did not support or cause dependence in rats. This compound, however, appeared to be a typical narcotic agent in morphine-dependent monkeys.

Acetates↗
PubMed1979

Synthesis and pharmacologic characterization of an alkylating analogue (chlornaltrexamine) of naltrexone with ultralong-lasting narcotic antagonist properties.

Chlornaltrexamine (CNA) produces ultralong-lasting (3--6 days) narcotic antagonism in mice and persistent stereospecific binding to rat-brain homogenate. Protection studies in mice suggest that CNA mediates its narcotic antagonist effects by interacting with the same receptors that are occupied by naloxone. A single icv dose of CNA also has been found to inhibit the development of physical dependence in mice for at least 3 days. These studies suggest that CNA exerts its sustained effects by selective covalent association with opioid receptors.

Alkylating Agents↗
PubMed2005

Structural alerts--a new classification model to discriminate excess toxicity from narcotic effect levels of organic compounds in the acute daphnid assay.

Quantitative and qualitative structure-activity relationships (QSARs) have a great potential to support the risk assessment of chemicals, provided there are tools available that allow evaluation of the suitability of QSARs for the compounds of interest. In this context, a pragmatic approach is to discriminate excess toxicity from narcotic effect levels, because the latter can be estimated from QSARs and thus have a low priority for experimental testing. To develop a respective scheme for the acute daphnid toxicity as one of the primary ecotoxicological endpoints, 1067 acute toxicity data entries for 380 chemicals involving the daphnid species Daphnia magna were taken from the on-line literature, and quality checks such as water solubility were employed to eliminate apparently odd data entries. For 36 known narcotics with LC50 values referring to D. magna, a reference baseline QSAR is derived. Compounds with LC50 values above a certain threshold defined relative to their predicted baseline toxicity are classified as exerting excess toxicity. Three simple discrimination schemes are presented that enable the identification of excess toxicity from structural alerts based on the presence or absence of certain heteroatoms and their chemical functionality. Moreover, a two-step classification approach is introduced that enables a prioritization of organic compounds with respect to their need for experimental testing. The discussion includes reaction mechanisms that may explain the association of structural alerts with excess toxicity, a comparison with predictions derived from mode of action-based classification schemes, and a statistical analysis of the discrimination performance in terms of detailed contingency table statistics.

Animal Testing Alternatives↗