heroin and morphine-6-glucuronide

This article reviews the pharmacokinetics of heroin after intravenous, oral, intranasal, intramuscular and rectal application and after inhalation in humans, with a special focus on heroin maintenance therapy in heroin dependent patients. In heroin maintenance therapy high doses pharmaceutically prepared heroin (up to 1000 mg/day) are prescribed to chronic heroin dependents, who do not respond to conventional interventions such as methadone maintenance treatment. Possible drug-drug interactions with the hydrolysis of heroin into 6-monoacetylmorphine and morphine, the glucuronidation of morphine and interactions with drug transporting proteins are described. Since renal and hepatic impairment is common in the special population of heroin dependent patients, specific attention was paid on the impact of renal and hepatic impairment. Hepatic impairment did not seem to have a clinically relevant effect on the pharmacokinetics of heroin and its metabolites. However, some modest effects of renal impairment have been noted, and therefore control of the creatinine clearance during heroin-assisted treatment seems recommendable.

Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Drug Interactions; Heroin; Humans; Kidney Diseases; Liver Diseases; Morphine; Morphine Derivatives

In several European countries and in Canada, clinical trials are being conducted in which heroin-addicted patients are treated with pharmaceutically prepared heroin in order to reduce the destructive behaviour that is so often associated with this drug.. To develop an integrated population pharmacokinetic model for heroin (diamorphine) and its pharmacodynamically active metabolites 6-acetylmorphine, morphine, morphine-3-glucuronide and morphine-6-glucuronide. Additionally, the influence on heroin pharmacokinetics of several covariates that are typical for this population was determined.. Plasma concentration data from 106 heroin-dependent patients in The Netherlands (74 heroin inhalers and 32 injectors) were obtained. The 'chasing the dragon' technique was used for inhalation, in which the fumes of heroin base, heated on aluminum foil, were inhaled. Heroin doses varied between 66 and 450 mg. Heroin, 6-acetylmorphine and morphine data were fitted simultaneously using sequential two-compartment models. Morphine-3-glucuronide and morphine-6-glucuronide data were fitted separately to one-compartment models. All data analysis was performed using nonlinear mixed-effect modelling.. The bioavailability of inhaled heroin was estimated to be 53% (95% CI 43.7, 62.3). The terminal half-lives of heroin and 6-acetylmorphine were estimated to be 7.6 and 21.8 minutes, respectively. The clearances of morphine and the morphine-glucuronides were estimated to be 73.6 L/h (95% CI 62.8, 84.4) and between 6 and 10 L/h, respectively. The terminal half-life of 6-acetylmorphine was 13% lower in cocaine users (p < 0.05). No other significant relationships between covariates and pharmacokinetic parameters were discovered.. Pharmacokinetic parameters of heroin and its five major metabolites were assessed simultaneously in one integrated model. Covariate analyses revealed that sex, bodyweight, benzodiazepine use and creatinine clearance (>60 mL/min) do not need to be taken into account in the medical prescription of pharmaceutically prepared heroin for the treatment of heroin dependency.

Topics: Administration, Inhalation; Adult; Analgesics, Opioid; Biological Availability; Female; Heroin; Heroin Dependence; Humans; Injections, Intravenous; Male; Middle Aged; Models, Biological; Morphine; Morphine Derivatives; Narcotics; Netherlands

After consumption of poppy seeds various substances were detected in urine or blood samples using an immunoassay and a sophisticated liquid chromatographic-tandem mass spectrometric procedure. These compounds are widely considered to be putative markers of heroin (HER) abuse whereas acetylcodeine was regarded as a marker for illicit preparations ("street HER"). Besides positive urinary opiate immunoassay results during a 48 hours monitoring period, peak concentrations of morphine (MOR), codeine and their glucuronides appeared 4 to 8 hours after ingestion of poppy seeds, and concentrations of total MOR higher than 10 microg/mL were observed. Also, in serum samples taken up to 6 hours after consumption, MOR glucuronides were found. Free MOR was only detected in traces (1 to 3 ng/mL) within 2 hours of consumption. In addition, 3 of 6 onsite opiate sweat tests revealed positive results 6.5 hours after ingestion. Furthermore, it was demonstrated that neither noscapine (NOS) nor papaverine (PAP) was detectable in urine or blood samples after the consumption of poppy seeds containing up to 94 microg NOS and up to 3.3 mug PAP. NOS and PAP were rapidly metabolized, whereas desmethylpapaverine and, especially, its glucuronide were found in urine samples of poppy seed consumers even 48 hours after consumption. According to these results PAP metabolites should not be regarded as markers of illicit HER abuse. In conclusion, only acetylcodeine can be regarded as a specific marker but has the problem of a short half-life. Therefore, we suggest that NOS and PAP, but not their metabolites, might be used cautiously as additional markers of illicit HER abuse as they have not been detected after oral intake of poppy seeds in normal doses. But it must be kept in mind that in some cases poppy seeds with an unusually high content of these alkaloids could be available, and that these substances are also agents in some pharmaceuticals.

Topics: Biomarkers; Chromatography, High Pressure Liquid; Codeine; Glucuronides; Heroin; Humans; Immunoassay; Mass Spectrometry; Morphine; Morphine Derivatives; Noscapine; Papaveraceae; Papaverine; Plant Preparations; Seeds; Substance Abuse Detection; Sweat; Time Factors

1. The pharmacokinetics of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) were studied in 19 ventilated newborn infants (24-41 weeks gestation) who were given a loading dose of 50 micrograms kg-1 or 200 micrograms kg-1 of diamorphine followed by an intravenous infusion of 15 micrograms kg-1 h-1 of diamorphine. Plasma concentrations of morphine, M3G and M6G were measured during the accrual to steady-state and at steady state of the diamorphine infusion. 2. Following both the 50 micrograms kg-1 or 200 micrograms kg-1 loading doses the mean steady-state plasma concentration (+/- s.d.) of morphine, M3G and M6G were 86 +/- 52 ng ml-1, 703 +/- 400 ng ml-1 and 48 +/- 28 ng ml-1 respectively and morphine clearance was found to be 4.6 +/- 3.2 ml min-1 kg-1. 3. M3G formation clearance was estimated to be 2.5 +/- 1.8 ml min-1 kg-1, and the formation clearance of M6G was estimated to be 0.46 +/- 0.32 ml min-1 kg-1. 4. M3G metabolite clearance was 0.46 +/- 0.60 ml min-1 kg-1, the elimination half-life was 11.1 +/- 11.3 h and the volume of distribution was 0.55 +/- 1.13 l kg-1. M6G metabolite clearance was 0.71 +/- 0.36 ml min-1 kg-1, the elimination half-life was 18.2 +/- 13.6 h and the volume of distribution was 1.03 +/- 0.88 l kg-1. 5. No significant effect of the loading dose (50 micrograms kg-1 or 200 micrograms kg-1) on the plasma morphine or metabolite concentrations or their derived pharmacokinetic parameters was found. 6. We were unable to identify correlations between gestational age of the infants and any of the determined pharmacokinetic parameters. 7. M3G: morphine and M6G: morphine steady-state plasma concentration ratios were 11.0 +/- 10.8 and 0.8 +/- 0.8, respectively. 8. The metabolism of morphine in neonates, in terms of the respective contributions of each glucuronide pathway, was similar to that in adults.

Topics: Analgesics, Opioid; Half-Life; Heroin; Humans; Infant, Newborn; Infant, Premature; Infusions, Intravenous; Morphine; Morphine Derivatives

The USA and numerous other countries worldwide are currently experiencing a public health crisis due to the abuse of heroin and illicitly manufactured fentanyl. We have developed a liquid chromatography tandem mass spectrometry (LC-MS-MS)-based method for the detection of morphine, fentanyl and their metabolites, including morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G), normorphine, norfentanyl and deuterated internal standards in limited sample volumes with the limit of detection of 5.0/0.5 ng/mL (morphine, M3G, M6G, normorphine/fentanyl, norfentanyl). The inter-assay precision (%CV) was less than 12% for all assays, and the inter-assay bias (%) was less than 5%. The ruggedness of the method, dilution effect and carryover were also investigated as part of the study. The simultaneous quantification of morphine, fentanyl and its metabolites via this simple and time- and cost-efficient method could be successfully applied to samples taken for pharmacokinetic evaluation (antemortem and postmortem) after a single dose of morphine or co-administration of morphine with other drugs (e.g., fentanyl) in rats.

Topics: Animals; Chromatography, Liquid; Fentanyl; Heroin; Morphine; Morphine Derivatives; Rats; Reproducibility of Results; Substance Abuse Detection; Tandem Mass Spectrometry

Heroin abuse is a serious problem that endangers human health and affects social stability. Though often being used as confirmation of heroin use, 6-monoacetylmorphine (6-MAM) has limitations due to its short detection window. To compare the detection windows of heroin metabolites (morphine (MOR), 6-MAM, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G)) in human urine, an automated online solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and fully validated. The limits of detections (LODs) of the four metabolites were in the range of 1.25-5 ng/mL. Intra and inter-day precision for all the metabolites was 0.4-6.7% and 1.8-7.3%, respectively. Accuracy ranged from 92.9 to 101.7%. This method was then applied to the analysis of urine samples of 20 male heroin abusers. M3G was detected 9-11 days after admission to the drug rehabilitation institute in 40% of heroin users while MOR or M6G was not always detected. The detection window of M3G was thus the longest. Furthermore, M3G had a much higher concentration than MOR and M6G. Therefore, M3G could provide diagnostic information with regard to heroin exposure in the combination with other clues (e.g., heroin seizures at the scene).

Topics: Chromatography, High Pressure Liquid; Chromatography, Liquid; Heroin; Heroin Dependence; Humans; Limit of Detection; Morphine Derivatives; Solid Phase Extraction; Substance Abuse Detection; Tandem Mass Spectrometry

Brain tissue is a useful supplement to blood in postmortem investigations, but reference concentrations are scarce for many opioids. Heroin cases may be difficult to distinguish from morphine cases as heroin and its metabolites are rapidly degraded. We present concentrations from brain and blood and brain-blood ratios of 98 cases where morphine was quantified. These cases were grouped according to the cause of death: A: The compound was solely assumed to have caused a fatal intoxication. B: The compound presumably contributed to a fatal outcome in combination with other drugs, alcohol or disease. C: The compound was not regarded to be related to the cause of death. The cases were further classified as heroin cases if 6-acetyl-morphine or noscapine were detected. The analyses were carried out using solid-phase extraction or protein precipitation followed by ultra high-performance liquid chromatography coupled to mass spectrometry. The average brain-blood ratios of morphine were 1.2 and 1.8 for 69 morphine and 29 heroin cases, respectively. Differences in the brain-blood ratios were found for cases where heroin and morphine were involved in the cause of death, either in combination or on its own (P<0.001 and P=0.004, respectively). However, the overlap between morphine and heroin cases precludes the use of the brain-blood ratio to distinguish heroin from morphine intake. Morphine-6-glucuronide and 6-acetyl-morphine were quantified in brain and blood in a subset of the samples, yielding median brain-blood ratios of 5.1 and 8.3, respectively. The brain concentrations may aid the toxicological investigation in cases where heroin or morphine intoxications are suspected, but blood is not available.

Topics: Brain Chemistry; Chromatography, Liquid; Drug Overdose; Forensic Toxicology; Heroin; Humans; Mass Spectrometry; Morphine; Morphine Derivatives; Narcotics; Noscapine; Poisoning

In heroin-related deaths, it is often of interest to determine the approximate time span between intake of heroin and death, and to decide whether heroin or other opioids have been administered. In some autopsy cases, peripheral blood cannot be sampled due to decomposition, injuries or burns. The aim of the present study was to investigate whether measurements of heroin metabolites in matrices other than peripheral blood can be used to differentiate between rapid and delayed heroin deaths, and if morphine/codeine ratios measured in other matrices can separate heroin from codeine intakes.. In this study, we included 51 forensic autopsy cases where morphine was detected in peripheral blood. Samples were collected from peripheral and cardiac blood, pericardial fluid, psoas and lateral vastus muscles, vitreous humor and urine. The opioid analysis included 6-acetylmorphine (6-AM), morphine, morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G) and codeine. Urine was only used for qualitative detection of 6-AM. 45 heroin-intake cases were divided into rapid deaths (n=24), based on the detection of 6-AM in blood, or delayed deaths (n=21), where 6-AM was detected in at least one other matrix but not in blood. An additional 6 cases were classified as codeine-intake cases, based on a morphine/codeine ratio below unity (<1) in peripheral blood, without detecting 6-AM in any matrix.. The median morphine concentrations were significantly higher in the rapid compared with the delayed heroin deaths in all matrices (p=0.004 for vitreous humor and p<0.001 for the other matrices). In the rapid heroin deaths, the M3G/morphine concentration ratios were significantly lower than in the delayed deaths both in peripheral and cardiac blood (p<0.001), as well as in pericardial fluid (p<0.001) and vitreous humor (p=0.006), but not in muscle. The morphine/codeine ratios measured in cardiac blood, pericardial fluid and the two muscle samples resembled the ratios in peripheral blood, although codeine was less often detected in other matrices than peripheral blood.. Measurements of heroin-metabolites in cardiac blood, pericardial fluid and vitreous humor provide information comparable to that of peripheral blood regarding rapid and delayed heroin deaths, e.g. M3G/morphine ratios <2 indicate a rapid death while ratios >3 indicate a delayed death. However, considerable overlap in results from rapid and delayed deaths was observed, and measurements in muscle appeared less useful. Furthermore, matrices other than peripheral blood can be used to investigate morphine/codeine ratios, but vitreous humor seems less suited.

Topics: Codeine; Drug Overdose; Forensic Toxicology; Heroin; Heroin Dependence; Humans; Morphine; Morphine Derivatives; Muscle, Skeletal; Pericardial Fluid; Postmortem Changes; Time Factors; Vitreous Body

The feasibility of intervention in heroin overdose is of clinical importance. The presence of 6-monoacetyl morphine (6MAM) in the blood is suggestive of survival times of less than 20-30 minutes following heroin administration. The study aimed to determine the proportions of cases in which 6MAM was present, and compare concentrations of secondary metabolites and circumstances of death by 6MAM status.. Analysis of cases of heroin-related death presenting to the Department of Forensic Medicine Sydney, 1 January 2013-12 December 2014.. Sydney, Australia.. A total of 145 cases. The mean age was 40.5 years and 81% were male.. Concentrations of 6MAM, free morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G). Circumstances of death included bronchopneumonia, apparent sudden collapse, location and other central nervous system (CNS) depressants.. 6MAM was detected in 43% [confidence interval (CI) = 35-51%] of cases. The median free morphine concentration of 6MAM-positive cases was more than twice that of cases without 6MAM (0.26 versus 0.12 mg/l). 6MAM-positive cases also had lower concentrations of the other major heroin metabolites: M3G (0.05 versus 0.29 mg/l), M6G (0.02 versus 0.05 mg/l) with correspondingly lower M3G/morphine (0.54 versus 2.71) and M6G/morphine (0.05 versus 0.50) ratios. Significant independent correlates of 6MAM were a higher free morphine concentration [odds ratio (OR) = 1.7], a lower M6G/free morphine ratio (OR = 0.5) and signs of apparent collapse (OR = 6.7).. In heroin-related deaths in Sydney, Australia during 2013 and 2014, 6- monoacetyl morphine was present in the blood in less than half of cases, suggesting that a minority of cases had survival times after overdose of less than 20-30 minutes. The toxicology of heroin metabolites and the circumstances of death were consistent with 6- monoacetyl morphine as a proxy for a more rapid death.

Topics: Adolescent; Adult; Australia; Autopsy; Drug Overdose; Female; Heroin; Humans; Male; Middle Aged; Morphine; Morphine Derivatives; Narcotics; Survival Rate; Young Adult

Ethanol and heroin are both depressant drugs on the central nervous system, and combined use is known to be dangerous due to pharmacodynamic interactions, leading to an even higher risk of respiratory depression and death. In addition, previous studies have suggested a pharmacokinetic interaction between ethanol and the metabolism of heroin. The aim of the present study was to investigate if there was a pharmacokinetic interaction between heroin and ethanol, by comparing concentrations of heroin metabolites in cases with and without ethanol, as detected in blood samples collected from a large material of forensic autopsy cases.. The material consisted of 1583 forensic autopsy cases, all containing 6-monoacetylmorphine (6-MAM), as evidence of heroin intake, in either blood or urine samples, from the time period between the 1st of January 2000 and the 31st of December 2012. Due to the high risk of post-mortem ethanol formation in cases revealing blood ethanol concentrations between 0.1 and 0.3‰, these cases were excluded from the study, along with cases where the analysis for ethanol was missing. After this exclusion of cases, the material (n=1474) was divided into two groups; one group where ethanol was not detected in blood (n=1160), and another group where ethanol was detected in blood at or above the concentration of 0.4‰ (n=314). Furthermore, the material was also divided into two other subgroups; one group where 6-MAM was detected in blood samples, indicating a very recent intake of heroin, and another group where 6-MAM was detected in the urine, but not in blood, indicating a less recent heroin intake.. The concentration ratios of morphine/6-MAM, morphine-3-glucuronide (M3G)/morphine, and morphine-6-glucuronide (M6G)/morphine in blood samples, were all significantly lower in the ethanol positive cases compared with that of the ethanol negative cases. For the subgroup of cases revealing a very recent intake of heroin (n=645), only the morphine/6-MAM ratio was significantly lower in the ethanol positive cases than in the ethanol negative cases. For the subgroup of cases with a less recent heroin intake (n=817), lower M3G/morphine and M6G/morphine ratios were found among the ethanol positive cases.. The results indicate that ethanol inhibits two steps in the heroin metabolism; the hydrolysis of 6-MAM to morphine, and the glucuronidation of morphine to M3G and M6G. This pharmacokinetic interaction could further complicate the outcome after combined use of heroin and ethanol, in addition to the already well-known pharmacodynamic interactions.

Topics: Central Nervous System Depressants; Drug Interactions; Ethanol; Forensic Toxicology; Heroin; Humans; Morphine Derivatives; Narcotics

Heroin is rapidly metabolized to morphine that in turn is transformed into morphine-3-glucuronide (M3G), an inactive metabolite at mu-opioid receptor (MOR), and morphine-6-glucuronide (M6G), a potent MOR agonist. We have found that rats that had received repeated intraperitoneal injections of heroin exhibit measurable levels of M6G (which is usually undetectable in this species).. The goal of the present study was to investigate whether M6G synthesis can be induced by intravenous (i.v.) heroin self-administration (SA).. Rats were trained to self-administer either heroin (50 μg/kg per infusion) or saline for 20 consecutive 6-h sessions and then challenged with an intraperitoneal challenge of 10 mg/kg of heroin. Plasma levels of heroin, morphine, 6-mono-acetyl morphine, M3G, and M6G were quantified 2 h after the challenge. In vitro morphine glucuronidation was studied in microsomal preparations obtained from the liver of the same rats.. Heroin SA induced the synthesis of M6G, as indicated by detectable plasma levels of M6G (89.7 ± 37.0 ng/ml vs. 7.35 ± 7.35 ng/ml after saline SA). Most important, the in vitro V (max) for M6G synthesis was correlated with plasma levels of M6G (r (2) = 0.78). Microsomal preparations from saline SA rats produced negligible amounts of M6G.. Both in vivo and in vitro data indicate that i.v. heroin SA induces the synthesis of M6G. These data are discussed in the light of previous studies conducted in heroin addicts indicating that in humans heroin enhances the synthesis of the active metabolite of heroin and morphine.

Topics: Animals; Heroin; Infusions, Intravenous; Injections, Intraperitoneal; Male; Microsomes, Liver; Morphine Derivatives; Rats; Rats, Sprague-Dawley; Self Administration

Topics: Clinical Competence; Expert Testimony; Forensic Toxicology; Heroin; Humans; Morphine; Morphine Derivatives; Narcotics; Suicide, Assisted; Terminally Ill

Liver metabolism of morphine leads to the formation of morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G), the latter possessing strong opioid activity that however differs from that of the parent compound. In previous studies conducted in rats we have shown that repeated in vivo exposure to phenanthrene class of mu opioid receptor (MOR) agonists or antagonists (heroin, morphine, and naltrexone), but not to non-phenanthrene class of MOR agonist methadone, affects morphine glucuronidation by liver microsomes.. In the present study, we measured the in vitro formation of M3G and M6G by rat hepatocytes incubated for 120 min with morphine (0.1-1.0 mM) after 72h pre-incubation with one of the following MOR agonists: heroin (3.3 or 6.6 microM), morphine (7.8 microM), or methadone (12 microM). The MOR antagonist naltrexone (10 or 25 microM) was also tested, alone or in combination with heroin. The amount of M3G and M6G synthesized was then measured by HPLC method.. Heroin inhibited M3G synthesis and induced the formation of M6G, which under basal conditions is not synthesized in rats. Heroin effects were not blocked by naltrexone. Morphine, but not methadone, produced effects similar to those of heroin but more modest in intensity. Pre-incubation with naltrexone alone slightly increased M3G synthesis, but had no effect on M6G formation.. These results are in agreement with those of previous ex vivo studies and indicate that exposure to heroin or, to a lesser extent, morphine, can affect morphine glucuronidation via direct non-opioid actions on the hepatocytes.

Topics: Analgesics, Opioid; Animals; Cell Separation; Cells, Cultured; Chromatography, High Pressure Liquid; Half-Life; Hepatocytes; Heroin; In Vitro Techniques; Male; Morphine Derivatives; Naltrexone; Narcotic Antagonists; Rats; Rats, Sprague-Dawley

Heroin is rapidly metabolized to morphine that in turn is transformed in morphine-3-glucuronide (M3G), an inactive metabolite, and morphine-6-glucuronide (M6G), a potent mu-opioid receptor (MOR) agonist. We have found that heroin addicts exhibit higher M6G/M3G ratios relative to morphine-treated control subjects. We have also shown that heroin-treated rats exhibit measurable levels of M6G (which is usually undetectable in this species) and reduced levels of M3G.. We investigated the role of MOR in these effects of heroin, by examining the effects of methadone, a MOR agonist, and of naltrexone, a MOR antagonist, on morphine glucuronidation. We also investigated the effects of alcohol, which is known to alter drug metabolism and is frequently coabused by heroin addicts.. Morphine glucuronidation was studied in liver microsomes obtained from rats exposed daily for 10 days to saline, heroin (10 mg/kg, i.p.), naltrexone (20-40 mg/kg, i.p.), heroin + naltrexone (10 mg/kg+20-40 mg/kg, i.p.), methadone (5-20 mg/kg, i.p.), or 10% ethanol.. Heroin induced the synthesis of M6G and decreased the synthesis of M3G. Naltrexone exhibited intrinsic modulatory activity on morphine glucuronidation, increasing the synthesis of M3G via a low-affinity/high-capacity reaction characterized by positive cooperativity. The rate of M3G synthesis in the heroin + naltrexone groups was not different from that of the naltrexone groups. Methadone and ethanol induced a modest increase in M3G synthesis and had no effect on M6G synthesis.. The effects of heroin on morphine glucuronidation are not shared by methadone or alcohol (two drugs that figure prominently in the natural history of heroin addiction) and do not appear to depend on the activation of MOR.

Topics: Animals; Ethanol; Heroin; Heroin Dependence; Male; Methadone; Microsomes, Liver; Morphine; Morphine Derivatives; Naltrexone; Rats; Rats, Sprague-Dawley; Receptors, Opioid, mu

3-O-Methylnaltrexone (3-MNTX), a putative antagonist of morphine-6-beta-d-glucuronide (M6G) receptors, has been reported to block the behavioral effects of heroin at doses that do not block those of morphine, suggesting that M6G receptors may play a unique role in the addictive properties of heroin. This study investigated the effects of 3-MNTX in monkeys trained to discriminate i.v. heroin from vehicle or to self-administer i.v. heroin under a progressive-ratio schedule. Additional in vitro studies determined the effects of 3-MNTX and reference drugs on adenylyl cyclase activity in caudate-putamen membranes of monkeys and rats. In drug discrimination experiments, heroin, morphine, and M6G substituted for heroin in all subjects, whereas 3-MNTX substituted for heroin in one-half the monkeys tested. In these latter monkeys, the effects of 3-MNTX were antagonized by naltrexone, and pretreatment with 3-MNTX enhanced the effects of heroin, M6G, and morphine, indicative of micro-agonist activity. In monkeys showing no substitution of 3-MNTX for heroin, 3-MNTX antagonized the effects of heroin, M6G, and morphine. In self-administration experiments, heroin and 3-MNTX maintained injections per session significantly above those maintained by vehicle when the initial response requirement (IRR) was low; only heroin maintained significant self-administration when the IRR was high. In vitro, 3-MNTX inhibited adenylyl cyclase activity in both monkey and rat brain membranes. The degree of inhibition produced by 3-MNTX was less than that produced by the full agonist [d-Ala(2),N-Me-Phe(4),Gly(5)-ol]-enkephalin (DAMGO). The results suggest that 3-MNTX functions primarily as a partial agonist at micro-receptors in monkeys and do not support a singular role for M6G receptors in the abuse-related effects of heroin.

Topics: Adenylyl Cyclases; Animals; Cocaine; Discrimination Learning; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; Heroin; Heroin Dependence; Macaca mulatta; Male; Morphine; Morphine Derivatives; Naltrexone; Narcotics; Quaternary Ammonium Compounds; Receptors, Opioid, mu; Self Administration

In the body, heroin is rapidly transformed to 6-acetylmorphine (6-AM) and then to morphine, that in turn is mainly metabolized to morphine-3-glucuronide (M3G) and, at lesser extent, to morphine-6-glucuronide (M6G). Unlike M3G, M6G is a potent opioid agonist. Intravenous heroin abusers (IHU) are exposed to a wide array of drugs and contaminants that might affect glucuronidation.. We assessed plasma and urine concentrations of M3G and M6G in four groups of subjects: the first two included long-term IHU either exposed to street heroin ( n=8) or receiving a single IV injection of morphine ( n=4), while the other two groups included non-IHU patients receiving acute IV ( n=8) or chronic oral ( n=6) administrations of morphine.. After solid phase extraction plasma and urine concentrations of morphine metabolites were determined by HPLC analyses.. M3G accounted for the greater part of morphine glucuronides detected in body fluids of non-IHU patients treated with morphine. This pattern of metabolism remained stable across 15 days of oral administration of incremental doses of morphine. In contrast, the two groups of IHU (street heroin taking or morphine-treated subjects) showed a reduction of blood and urine M3G concentrations in favor of M6G. Consequently, M6G/M3G ratio was significantly higher in the two IHU groups in comparison with the non-IHU groups.. Chronic exposure to street heroin causes a relative increase in concentrations of the active metabolite, M6G. Since the pattern of M6G action seems closer to heroin than to morphine, the increased synthesis of M6G observed in IHU may prolong the narrow window of heroin effects.

Topics: Adult; Aged; Analgesics, Opioid; Analysis of Variance; Chromatography, High Pressure Liquid; Drug Administration Schedule; Female; Heroin; Heroin Dependence; Humans; Male; Middle Aged; Morphine; Morphine Derivatives; Narcotics; Time Factors

After absorption, heroin is transformed into mono-acetyl-morphine and then into morphine. Morphine, in turn, is metabolized to morphine-3-glucuronide (M3G), an inactive compound, and morphine-6-glucuronide (M6G), a potent opioid agonist. Thus, changes in the rate of formation of M6G may alter the pharmacological consequences of a treatment with heroin or morphine. In this study, we investigate the effect of repeated exposures (10 daily i.p. injections) to heroin, morphine, cadmium (which has been previously shown to inhibit M3G formation in vitro), or heroin + cadmium on morphine glucuronidation both in vivo and ex vivo (i.e., microsomal preparation obtained from rats treated in vivo). Repeated heroin (2.5, 5.0, and 10 mg/kg) increased plasma levels of M6G (which was undetectable in all other groups) and reduced those of M3G. Also, the microsomal preparations obtained from the liver of repeated heroin rats, when incubated with morphine, yielded significant amounts of M6G (which was undetectable in all other groups) and decreased levels of M3G relative to the control groups. These effects were reversible upon discontinuation of heroin administration. In contrast, repeated morphine (10, 20, and 40 mg/kg) only slightly reduced M3G formation at the dose of 40 mg/kg. Repeated cadmium (5, 15, and 45 microg/kg) reduced the rate of M3G formation without inducing M6G synthesis. The effects of the repeated coadministration of heroin (10 mg/kg) and cadmium (15 microg/kg) were virtually identical to those of repeated heroin alone. In summary, repeated exposure of rats to heroin can shift morphine glucuronidation toward the formation of the active metabolite M6G.

Topics: Analgesics, Opioid; Animals; Cadmium; Chromatography, High Pressure Liquid; Guinea Pigs; Heroin; Male; Microsomes, Liver; Morphine; Morphine Derivatives; Rats; Rats, Sprague-Dawley

Morphine produces analgesia by activating mu opioid receptors encoded by the MOR-1 gene. Although morphine-6 beta-glucuronide (M6G), heroin and 6-acetylmorphine also are considered mu opioids, recent evidence suggests that they act through a distinct receptor mechanism. We examined this question in knockout mice containing disruptions of either the first or second coding exon of MOR-1. Mice homozygous for either MOR-1 mutation were insensitive to morphine. Heroin, 6-acetylmorphine and M6G still elicited analgesia in the exon-1 MOR-1 mutant, which also showed specific M6G binding, whereas M6G and 6-acetylmorphine were inactive in the exon-2 MOR-1 mutant. These results provide genetic evidence for a unique receptor site for M6G and heroin analgesia.

Topics: Analgesics, Opioid; Animals; Drug Resistance; Exons; Heroin; Mice; Mice, Inbred C57BL; Mice, Knockout; Morphine Derivatives; Receptors, Opioid, mu; Transcription, Genetic

The development of an immunoaffinity-based extraction method for the determination of morphine and its glucuronides in human blood is described. For the preparation of an immunoadsorber, specific antisera (polyclonal, host: rabbit) against morphine, morphine-3-glucuronide and morphine-6-glucuronide were coupled to 1,1'-carbonyldiimidazole-activated tris-acrylgel and used for immunoaffinity extraction of morphine and its glucuronides from coronary blood. The resulting extracts were analysed by HPLC with native fluorescence detection. The mean recoveries from spiked blood samples were 71%, 76% and 88% for morphine, morphine-3-glucuronide and morphine-6-glucuronide, respectively. The limit of detection was 3 ng/g blood and the limit of quantitation was 10 ng/g blood for all three analytes. The results of the analysis of coronary blood samples from 23 fatalities due to heroin are presented.

Topics: Chromatography, Affinity; Chromatography, High Pressure Liquid; Drug Overdose; Heroin; Humans; Morphine; Morphine Derivatives; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Fluorescence

In mice, 3-O-methylnaltrexone blocks the analgesic actions of morphine-6beta-glucuronide and heroin at doses which are inactive against morphine. We found a similar selectivity in rats. 3-O-Methylnaltrexone antagonized the analgesic actions of 6-acetylmorphine in Sprague-Dawley rats and heroin in Wistar rats at doses that were inactive against morphine. Inclusion of a fixed dose of 3-O-methylnaltrexone significantly shifted the analgesic dose-response curves for 6-acetylmorphine and heroin without altering the morphine dose-response curves. In a self-administration model, 3-O-methylnaltrexone treatment significantly increased both heroin and morphine intake during the first hour, suggestive of an antagonist effect. This effect at doses of 3-O-methylnaltrexone which were inactive against morphine analgesia implied a role for the morphine-6beta-glucuronide opioid receptor in the reinforcing properties of heroin and morphine.

Topics: Animals; Conditioning, Operant; Dose-Response Relationship, Drug; Heroin; Injections, Subcutaneous; Male; Morphine; Morphine Derivatives; Naltrexone; Narcotic Antagonists; Narcotics; Pain Measurement; Quaternary Ammonium Compounds; Rats; Rats, Sprague-Dawley; Rats, Wistar; Self Administration

A 17-year-old girl was found dead in a public toilet with fresh needle puncture marks. She was 18-20 weeks pregnant with a male fetus. Drug screening of her blood and urine indicated recent heroin use. Chronic drug use was confirmed by hair analysis. Amniotic fluid as well as fetal and maternal tissues and body fluids were analyzed by GC/MS and HPLC. All the fetal specimens were investigated, and the following levels of drugs were found: 6-monoacetyl-morphine (blood: 152 ng/g; amniotic fluid: 128 ng/g; brain: 140 ng/g; lung: 110 ng/g; liver: 2 ng/g; kidney: 40 ng/g), morphine (blood: 1360 ng/g; amniotic fluid: 604 ng/g; brain: 710 ng/g; lung: 1030 ng/g; liver: 2060 ng/g; kidney: 1100 ng/g), codeine (blood: 70 ng/g; brain: 60 ng/g; lung: 60 ng/g; liver: 90 ng/g; kidney: 70 ng/g), and morphine-3-glucuronide (amniotic fluid: 209 ng/g; brain: 170 ng/g; lung: 325 ng/g; kidney: 231 ng/g). Morphine-6-glucuronide was present in the maternal circulation but could not be detected in the fetal circulation.

Topics: Adolescent; Amniotic Fluid; Autopsy; Body Fluids; Codeine; Fatal Outcome; Female; Fetus; Gas Chromatography-Mass Spectrometry; Hair; Heroin; Humans; Male; Maternal-Fetal Exchange; Morphine Derivatives; Opioid-Related Disorders; Pregnancy; Pregnancy Complications; Pregnancy Trimester, Second; Tissue Distribution

Recent reports suggest that heroin and its metabolite morphine 6beta-glucuronide can produce analgesia independent of the morphine-preferring mu-opioid receptor. We have tested heroin and morphine 6beta-glucuronide analgesia in wild-type, homozygous and heterozygous mu-opioid receptor knockout mice. Homozygotes display no heroin or morphine 6beta-glucuronide analgesia. Heterozygous mice with one mu-opioid receptor gene copy reveal reduced heroin and morphine 6beta-glucuronide analgesia. The mu-opioid receptor-dependence of heroin and morphine 6beta-glucuronide fails to support a requirement for a heroin-specific opiate receptor subtype.

Topics: Analgesia; Analgesics, Opioid; Animals; Heroin; Homozygote; Mice; Mice, Knockout; Morphine Derivatives; Receptors, Opioid, mu

Topics: Adult; Drug Overdose; Heroin; Humans; Male; Morphine; Morphine Derivatives; Postmortem Changes; Tissue Distribution

A rapid and selective reversed-phase high-performance liquid chromatographic assay with gradient elution and diode-array detection for diacetylmorphine, morphine, codeine, and their free and glucuronidated metabolites in plasma, was developed. After addition of ethylmorphine as internal standard the plasma samples were extracted using C18 ODS-2 solid-phase columns with a recovery better than 80%. The limit of quantitation using an injection volume of 2 microl was 25 ng/ml for each compound. The intra- and inter-day precision was better than 5%. The described method cannot only be used for pharmacokinetic studies but also for intoxication cases to monitor a wide range of opiates.

Topics: Chromatography, High Pressure Liquid; Heroin; Humans; Injections, Intravenous; Morphine; Morphine Derivatives; Narcotics; Spectrophotometry, Ultraviolet

Recent work has suggested that heroin and morphine-6beta-glucuronide (M6G) both act through a novel mu opioid receptor subtype distinct from those mediating morphine's actions. This very high affinity 3H-M6G site is selectively competed by 3-methoxynaltrexone. In vivo, 3-methoxynaltrexone (2.5 ng, i.c.v.) selectively antagonizes the analgesic actions of heroin and M6G without interfering with mu (morphine and [D-Ala2,MePhe4,Gly(ol)5]enkephalin), delta ([D-Pen2,D-Pen5]enkephalin), kappa1 (U50,488H) or kappa3 (naloxone benzoylhydrazone) analgesia. In dose-response studies, 3-methoxynaltrexone (2.5 ng, i.c.v.) significantly shifted the ED50 values for heroin and its active metabolite, 6-acetylmorphine, without affecting the morphine curve. These results indicate that 3-methoxynaltrexone selectively blocks a novel 3H-M6G binding site which is responsible for the analgesic actions of heroin and M6G. This ability to selectively antagonize heroin actions opens new possibilities in the development of therapeutics for the treatment of opioid abuse.

Topics: Analgesia; Animals; Binding Sites; Binding, Competitive; CHO Cells; Cricetinae; Heroin; Male; Mice; Morphine; Morphine Derivatives; Naltrexone; Narcotic Antagonists; Receptors, Opioid, mu; Transfection; Tritium

For the interpretation of the concentration of morphine in blood samples of heroin consumers information about the concentration of the analgesic active morphine metabolite morphine-6-glucuronide is very important. Thus a simple but specific clean-up procedure based on immuno-affinity chromatography is presented for the extraction of morphine, morphine-3-glucuronide and morphine-6-glucuronide from whole blood in cases of fatal heroin overdose. The preparation of the immunoabsorber by immobilization of antibodies against morphine-3-BSA and morphine-6-KLH with carbonyldiimidazole-activated trisacrylgel is described. The separation of the extracts is achieved by HPLC using native fluorescence detection. The limits of detection for this method are 10ng for morphine and morphine glucuronides/g blood. The results for the concentration of morphine and morphine glucuronides in blood from seven cases of heroin overdose are presented. By calculating the quotients for the concentrations of morphine-6-glucuronide/morphine the time elapsed since the last intake of heroin is estimated.

Topics: Antibodies; Chromatography, Affinity; Chromatography, High Pressure Liquid; Drug Overdose; Heroin; Heroin Dependence; Humans; Immunosorbents; Morphine Derivatives; Postmortem Changes; Time Factors

Morphine, morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G), and 6-monoacetylmorphine (6-MAM) were isolated from body fluids using solid-phase extraction and determined by means of atmospheric pressure chemical ionization-mass spectrometry-liquid chromatography (APCI-LC-MS) in selected ion monitoring mode. The following ions were monitored: m/z 286 for morphine; m/z 286 and 462 for M3G and M6G; m/z 211, 268, and 328 for 6-MAM; and m/z 289 for morphine-d3 (internal standard). The recoveries ranged from 82 to 89% The limits of detection were as follows: 0.1 ng/mL (morphine), 0.5 ng/mL (6-MAM), and 1 ng/mL (M3G and M6G). The analytes were determined in samples taken from 21 heroin-overdose victims. Twenty-one blood samples, 11 cerebrospinal fluid (CSF) samples, 12 vitreous humor (VH) samples, and 6 urine samples were investigated. Blood concentrations (ng/mL) of morphine ranged from 8 to 1539, of M3G from 111 to 941, of M6G from 32 to 332, and of 6-MAM from 0 to 73. The levels of morphine were correlated with glucuronide values and with 6-MAM. The concentrations of morphine, M3G, and M6G in CSF were, as a rule, lower than in blood and lower in VH than in CSF. The concentrations of morphine and molar ratios of M6G-morphine in blood and CSF were correlated. Low ratios of M3G-morphine and M6G-morphine in blood of heroin-overdose victims indicated short survival time after drug intake.

Topics: Adolescent; Adult; Atmospheric Pressure; Autopsy; Chromatography, Liquid; Female; Heroin; Heroin Dependence; Humans; Male; Mass Spectrometry; Morphine; Morphine Derivatives; Narcotics; Urine; Vitreous Body

Topics: Biological Transport; Chemical Phenomena; Chemistry, Physical; Chloroform; Hydrogen-Ion Concentration; Morphine Derivatives; Narcotics; Octanols; Potentiometry; Solutions; Solvents

The rapid metabolism of heroin to 6-acetylmorphine and its slower conversion to morphine has led many to believe that heroin and morphine act through the same receptors and that the differences between them are due to their pharmacokinetics. We now present evidence strongly implying that heroin and two potent mu drugs, fentanyl and etonitazine, act through a unique receptor mechanism similar to morphine-6 beta-glucuronide which is readily distinguished from morphine. Heroin, 6-acetylmorphine and morphine-6 beta-glucuronide show no analgesic cross tolerance to morphine in a daily administration paradigm, implying distinct receptors. Strains also reveal analgesic differences among the drugs. CXBK mice, which are insensitive to morphine, retain their analgesic sensitivity to heroin, 6-acetylmorphine, morphine-6 beta-glucuronide, fentanyl and etonitazine. Antisense mapping of the mu opioid receptor MOR-1 reveals that oligodeoxynucleotide probes against exon 2, which are inactive against morphine analgesia, block morphine-6 beta-glucuronide, heroin, fentanyl and etonitazine analgesia. Finally, an antisense probe targeting Gi alpha 1 blocks both heroin and morphine-6 beta-glucuronide, but not morphine, analgesia. These results indicate that heroin, 6-acetylmorphine, fentanyl and etonitazine all can produce analgesia through a novel mu analgesic system which is similar to that activated by morphine-6 beta-glucuronide.

Topics: Analgesics; Analgesics, Opioid; Animals; Down-Regulation; Drug Tolerance; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; Enkephalins; Heroin; Male; Mice; Mice, Inbred Strains; Morphine Derivatives; Oligonucleotides, Antisense; Receptors, Opioid; Receptors, Opioid, mu; Species Specificity

Topics: Analgesia; Heroin; Humans; Morphine; Morphine Derivatives; Time Factors

Topics: Heroin; Heroin Dependence; Humans; Morphine; Morphine Derivatives; Naloxone; Substance-Related Disorders