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Wilson LL, Chakraborty S, Eans SO, Cirino TJ, Stacy HM, Simons CA, Uprety R, Majumdar S, McLaughlin JP. Kratom Alkaloids, Natural and Semi-Synthetic, Show Less Physical Dependence and Ameliorate Opioid Withdrawal. Cell Mol Neurobiol 2021; 41:1131-1143. [PMID: 33433723 PMCID: PMC8164968 DOI: 10.1007/s10571-020-01034-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 12/21/2020] [Indexed: 01/13/2023]
Abstract
Chronic administration of opioids produces physical dependence and opioid-induced hyperalgesia. Users claim the Thai traditional tea "kratom" and component alkaloid mitragynine ameliorate opioid withdrawal without increased sensitivity to pain. Testing these claims, we assessed the combined kratom alkaloid extract (KAE) and two individual alkaloids, mitragynine (MG) and the analog mitragynine pseudoindoxyl (MP), evaluating their ability to produce physical dependence and induce hyperalgesia after chronic administration, and as treatments for withdrawal in morphine-dependent subjects. C57BL/6J mice (n = 10/drug) were administered repeated saline, or graded, escalating doses of morphine (intraperitoneal; i.p.), kratom alkaloid extract (orally, p.o.), mitragynine (p.o.), or MP (subcutaneously, s.c.) for 5 days. Mice treated chronically with morphine, KAE, or mitragynine demonstrated significant drug-induced hyperalgesia by day 5 in a 48 °C warm-water tail-withdrawal test. Mice were then administered naloxone (10 mg/kg, s.c.) and tested for opioid withdrawal signs. Kratom alkaloid extract and the two individual alkaloids demonstrated significantly fewer naloxone-precipitated withdrawal signs than morphine-treated mice. Additional C57BL/6J mice made physically dependent on morphine were then used to test the therapeutic potential of combined KAE, mitragynine, or MP given twice daily over the next 3 days at either a fixed dose or in graded, tapering descending doses. When administered naloxone, mice treated with KAE, mitragynine, or MP under either regimen demonstrated significantly fewer signs of precipitated withdrawal than control mice that continued to receive morphine. In conclusion, while retaining some liabilities, kratom, mitragynine, and mitragynine pseudoindoxyl produced significantly less physical dependence and ameliorated precipitated withdrawal in morphine-dependent animals, suggesting some clinical value.
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MESH Headings
- Analgesics, Opioid/administration & dosage
- Analgesics, Opioid/adverse effects
- Animals
- Male
- Mice
- Mice, Inbred C57BL
- Mitragyna
- Morphine Dependence/metabolism
- Morphine Dependence/prevention & control
- Morphine Dependence/psychology
- Pain Measurement/drug effects
- Pain Measurement/methods
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/metabolism
- Secologanin Tryptamine Alkaloids/administration & dosage
- Secologanin Tryptamine Alkaloids/adverse effects
- Secologanin Tryptamine Alkaloids/chemical synthesis
- Secologanin Tryptamine Alkaloids/isolation & purification
- Substance Withdrawal Syndrome/metabolism
- Substance Withdrawal Syndrome/prevention & control
- Substance Withdrawal Syndrome/psychology
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Affiliation(s)
- Lisa L Wilson
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Soumen Chakraborty
- Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Shainnel O Eans
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Thomas J Cirino
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Heather M Stacy
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Chloe A Simons
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA
| | - Rajendra Uprety
- Molecular Pharmacology and Chemistry Program and Department of Neurology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Susruta Majumdar
- Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Jay P McLaughlin
- Department of Pharmacodynamics, University of Florida, 1345 Center Drive, Gainesville, FL, 32610, USA.
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Avery BA, Boddu SP, Sharma A, Furr EB, Leon F, Cutler SJ, McCurdy CR. Comparative Pharmacokinetics of Mitragynine after Oral Administration of Mitragyna speciosa (Kratom) Leaf Extracts in Rats. Planta Med 2019; 85:340-346. [PMID: 30452072 DOI: 10.1055/a-0770-3683] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Kratom (Mitragyna speciosa) has been examined for its opioid activity, especially for the treatment of opioid withdrawal and pain. Mitragynine, the most abundant alkaloid in kratom, is thought to be the major psychoactive alkaloid. An HPLC method was developed for the quantification of mitragynine in kratom leaf extracts. In addition, a multiple reaction mode based UPLC-MS/MS method was developed and validated for the quantification of mitragynine in rat plasma. Pharmacokinetic studies were performed by comparing a single intravenous dose of mitragynine (5 mg/kg, mitragynine hydrochloride) to a single oral dose of mitragynine (20 mg/kg, mitragynine hydrochloride), lyophilized kratom tea, and the organic fraction of the lyophilized kratom tea at an equivalent mitragynine dose of 20 mg/kg in rats. After intravenous administration, mitragynine exhibited a biexponential decrease in the concentration-time profile, indicating the fast distribution of mitragynine from the systemic circulation or central compartment to the peripheral compartments. Mitragynine hydrochloride, lyophilized kratom tea, and the lyophilized kratom tea organic fraction were dosed orally and the absolute oral bioavailability of mitragynine in rats was found to be 1.5- and 1.8-fold higher than that of mitragynine dosed alone. The results provide evidence that an equivalent oral dose of the traditional preparation (lyophilized kratom tea) and formulated/manufactured products (organic fraction) of kratom leaves provide better systemic exposure of mitragynine than that of mitragynine dosed alone.
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Affiliation(s)
- Bonnie A Avery
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL, USA (present affiliation)
- Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA
| | - Sai P Boddu
- Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA
| | - Abhisheak Sharma
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL, USA (present affiliation)
- Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS, USA
| | - Edward B Furr
- Department of BioMolecular Sciences, School of Pharmacy, The University of Mississippi, University, MS, USA
| | - Francisco Leon
- Department of BioMolecular Sciences, School of Pharmacy, The University of Mississippi, University, MS, USA
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL, USA (present affiliation)
| | - Stephen J Cutler
- Department of BioMolecular Sciences, School of Pharmacy, The University of Mississippi, University, MS, USA
- College of Pharmacy, University of South Carolina, Columbia, SC, USA (present affiliation)
| | - Christopher R McCurdy
- Department of BioMolecular Sciences, School of Pharmacy, The University of Mississippi, University, MS, USA
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL, USA (present affiliation)
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Abdullah NH, Ismail S. Inhibition of UGT2B7 Enzyme Activity in Human and Rat Liver Microsomes by Herbal Constituents. Molecules 2018; 23:molecules23102696. [PMID: 30347696 PMCID: PMC6222696 DOI: 10.3390/molecules23102696] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 10/15/2018] [Accepted: 10/17/2018] [Indexed: 12/22/2022] Open
Abstract
The co-use of conventional drug and herbal medicines may lead to herb-drug interaction via modulation of drug-metabolizing enzymes (DMEs) by herbal constituents. UDP-glucuronosyltransferases (UGTs) catalyzing glucuronidation are the major metabolic enzymes of Phase II DMEs. The in vitro inhibitory effect of several herbal constituents on one of the most important UGT isoforms, UGT2B7, in human liver microsomes (HLM) and rat liver microsomes (RLM) was investigated. Zidovudine (ZDV) was used as the probe substrate to determine UGT2B7 activity. The intrinsic clearance (Vmax/Km) of ZDV in HLM is 1.65 µL/mg/min which is ten times greater than in RLM, which is 0.16 µL/mg/min. Andrographolide, kaempferol-3-rutinoside, mitragynine and zerumbone inhibited ZDV glucuronidation in HLM with IC50 values of 6.18 ± 1.27, 18.56 ± 8.62, 8.11 ± 4.48 and 4.57 ± 0.23 µM, respectively, hence, herb-drug interactions are possible if andrographolide, kaempferol-3-rutinoside, mitragynine and zerumbone are taken together with drugs that are highly metabolized by UGT2B7. Meanwhile, only mitragynine and zerumbone inhibited ZDV glucuronidation in RLM with IC50 values of 51.20 ± 5.95 μM and 8.14 ± 2.12 µM, respectively, indicating a difference between the human and rat microsomal model so caution must be exercised when extrapolating inhibitory metabolic data from rats to humans.
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Affiliation(s)
- Nurul Huda Abdullah
- Centre for Drug Research, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia.
| | - Sabariah Ismail
- Centre for Drug Research, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia.
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Yue K, Kopajtic TA, Katz JL. Abuse liability of mitragynine assessed with a self-administration procedure in rats. Psychopharmacology (Berl) 2018; 235:2823-2829. [PMID: 30039246 DOI: 10.1007/s00213-018-4974-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 07/12/2018] [Indexed: 11/26/2022]
Abstract
RATIONALE Substantial use of the plant kratom for psychoactive effects has driven interest in its abuse liability. Several place conditioning studies suggest abuse liability of the active ingredient mitragynine, though studies of its self-administration have not been published. METHODS Binding of mitragynine to rat brain mu, kappa, and delta opioid receptors was compared to that for heroin and morphine. Self-administration of mitragynine, heroin, methamphetamine, or saline was assessed during single-session substitutions in rats trained to self-administer methamphetamine (0.022 mg/kg/injection, i.v.) during 1-h daily sessions. RESULTS Mitragynine had > 2- or ~ 16-fold greater affinity for the mu opioid receptor than, respectively, for kappa or delta opioid receptors. Its affinity for the mu receptor was ~ 200-fold less than that for morphine. In rats trained to self-administer methamphetamine, saline substitutions significantly decreased the number of responses, whereas different doses of methamphetamine (0.002-0.068 mg/kg/injection) or heroin (0.001-0.03 mg/kg/injection) maintained self-administration with maximal responding at 0.022 or 0.01 mg/kg/injection, respectively. In contrast, no dose of mitragynine maintained response rates greater than those obtained with saline. Presession mitragynine treatment (0.1 to 3.0 mg/kg) decreased response rates maintained by heroin but had little effect on responding maintained by methamphetamine across the same range of doses. CONCLUSIONS These results suggest a limited abuse liability of mitragynine and potential for mitragynine treatment to specifically reduce opioid abuse. With the current prevalence of opioid abuse and misuse, it appears currently that mitragynine is deserving of more extensive exploration for its development or that of an analog as a medical treatment for opioid abuse.
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Affiliation(s)
- Kai Yue
- Wuhan Institute of Biomedical Science, Jianghan University, No. 8 Sanjiaohu Street, Wuhan, China
| | - Theresa A Kopajtic
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Baltimore, MD, 21224, USA
| | - Jonathan L Katz
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Baltimore, MD, 21224, USA.
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Singh D, Müller CP, Murugaiyah V, Hamid SBS, Vicknasingam BK, Avery B, Chear NJY, Mansor SM. Evaluating the hematological and clinical-chemistry parameters of kratom (Mitragyna speciosa) users in Malaysia. J Ethnopharmacol 2018; 214:197-206. [PMID: 29248450 DOI: 10.1016/j.jep.2017.12.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 12/11/2017] [Accepted: 12/13/2017] [Indexed: 06/07/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Kratom (Mitragyna speciosa Korth.) from the Rubiaceae family is an indigenous tropical medicinal tree of Southeast Asia. Kratom leaves have been used for decades in Malaysia and Thailand in traditional context for its perceived vast medicinal value, and as a mild stimulant among manual labourers. Kratom consumption has been reported to cause side-effects in kratom users. AIM OF THE STUDY To evaluate kratom's effects towards hematological and clinical-chemistry parameters among regular kratom users in Malaysia. METHODS A total of 77 subjects (n=58 regular kratom users, and n=19 healthy controls) participated in this cross-sectional study. All the surveys were conducted through face-to-face interview to elicit subject's socio-demographic characteristics and kratom use history. A full-blood test was also administered. Laboratory analysis was conducted using GC-MS to determine mitragynine content in the acquired kratom samples in order to relate mitragynine consumption with possible alterations in the blood parameters of kratom users. RESULTS Findings showed that there were no significant differences in the hematological and clinical-chemistry parameters of traditional kratom users and healthy controls, except for HDL and LDL cholesterol values; these were found to be above the normal reference range for the former. Similarly, long-term kratom consumption (>5 years), and quantity of daily kratom use (≥3 ½ glasses; mitragynine content 76.3-114.8mg) did not appear to alter the hematological and biochemical parameters of kratom users. CONCLUSION These data suggest that even long-term and heavy kratom consumption did not significantly alter the hematological and clinical-chemistry parameters of kratom users in a traditional setting.
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Affiliation(s)
- Darshan Singh
- Centre for Drug Research, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Vikneswaran Murugaiyah
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
| | - Shahrul Bariyah Sahul Hamid
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia
| | | | - Bonnie Avery
- College of Pharmacy, University of Florida, Gainesville 32610, United States
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Abstract
BACKGROUND Kratom (Mitragyna speciosa) is a psychoactive plant native to Southeastern Asia that is receiving increased international attention as a potential therapeutic agent. While much of the limited scientific research on kratom is focused on its analgesic potential, kratom use also has important risks and benefits in the domain of mental health. METHODS We conducted a comprehensive systematic review of all studies on kratom use and mental health published between January 1960 and July 2017. RESULTS Findings indicate kratom's potential as a harm reduction tool, most notably as a substitute for opioids among people who are addicted. Kratom also enhances mood and relieves anxiety among many users. For many, kratom's negative mental health effects - primarily withdrawal symptoms - appear to be mild relative to those of opioids. For some users, however, withdrawal is highly uncomfortable and maintaining abstinence becomes difficult. CONCLUSION Results inform clinicians working in the mental health and substance use fields, policy-makers, and researchers about the mental health effects of this plant.
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Affiliation(s)
- Marc T Swogger
- Department of Psychiatry, University of Rochester Medical 300 Center, Crittenden Blvd., Rochester, NY, USA.
| | - Zach Walsh
- Department of Psychology, University of British Columbia, 3333 University Way, Kelowna, BC, Canada
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Jamil MFA, Subki MFM, Lan TM, Majid MIA, Adenan MI. The effect of mitragynine on cAMP formation and mRNA expression of mu-opioid receptors mediated by chronic morphine treatment in SK-N-SH neuroblastoma cell. J Ethnopharmacol 2013; 148:135-143. [PMID: 23608241 DOI: 10.1016/j.jep.2013.03.078] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 03/25/2013] [Accepted: 03/28/2013] [Indexed: 06/02/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE [corrected] Mitragynine is an indole alkaloid compound of Mitragyna speciosa (M. speciosa) Korth. (Rubiaceae). This plant is native to the southern regions of Thailand and northern regions of Malaysia and is frequently used to manage the withdrawal symptoms in both countries. AIM OF STUDY To investigate the effect of mitragynine after chronic morphine treatment on cyclic AMP (cAMP) level and mRNA expression of mu-opioid receptor (MOR) in human neuroblastoma SK-N-SH cell. METHOD AND MATERIALS Mitragynine was isolated from the Mitragyna speciosa plant using the acid-base extraction method. The cAMP level upon forskolin stimulation in the cells was determined using the Calbiochem(®) Direct Immunoassay Kit. The mRNA expression of the MOR was carried out using quantitative RT-PCR. RESULT Cotreatment and pretreatment of morphine and mitragynine significantly reduced the production of cAMP level at a lower concentration of mitragynine while the higher concentration of this compound could lead to the development of tolerance and dependence as shown by the increase of the cAMP level production in foskolin stimulation. In MOR mRNA expression study, cotreatment of morphine with mitragynine significantly reduced the down-regulation of MOR mRNA expression as compared to morphine treatment only. CONCLUSION These finding suggest that mitragynine could possibly avoid the tolerance and dependence on chronic morphine treatment by reducing the up-regulation of cAMP level as well as reducing the down-regulation of MOR at a lower concentration of mitragynine.
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Affiliation(s)
- Mohd Fadzly Amar Jamil
- Malaysian Institute Pharmaceuticals and Nutraceuticals (IPharm), Ministry of Science, Technology and Innovation (MOSTI) Jalan Bukit Gambir, 11700 Gelugor Pulau Pinang, Malaysia
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Sabetghadam A, Ramanathan S, Sasidharan S, Mansor SM. Subchronic exposure to mitragynine, the principal alkaloid of Mitragyna speciosa, in rats. J Ethnopharmacol 2013; 146:815-823. [PMID: 23422336 DOI: 10.1016/j.jep.2013.02.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 02/06/2013] [Accepted: 02/08/2013] [Indexed: 06/01/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Mitragyna speciosa is a popular medicinal plant in Southeast Asia which is commonly used for its morphine-like effects. Although the analgesic properties of Mitragyna speciosa and its ability to ameliorate withdrawal signs after abrupt cessation of opioid abuse are well known, information about the long-term safety of the plant's active compounds is lacking. In this work, we evaluated the effects of sub-chronic exposure to mitragynine, the principal alkaloid of Mitragyna speciosa leaves in rats. MATERIALS AND METHODS Male and female Sprague-Dawley rats received three doses of mitragynine (1, 10, 100mg/kg, p.o) for 28 days respectively. Food intake and relative body weight were measured during the experiment. After completion of drug treatment biochemical, hematological, and histological analyses were performed. RESULTS No mortality was observed in any of the treatment groups. The groups of rats treated with the lower and intermediate doses showed no toxic effects during the study. However, the relative body weight of the group of female rats treated with the 100mg/kg dose was decreased significantly. Food intake also tended to decrease in the same group. Only relative liver weight increased after treatment with the high dose of mitragynine (100mg/ kg) in both the male and female treatment groups of rats. Biochemical and hematological parameters were also altered especially in high dose treatment group which corresponds to the histopathological changes. CONCLUSIONS The study demonstrated that mitragynine is relatively safe at lower sub-chronic doses (1-10mg/kg) but exhibited toxicity at a highest dose (sub-chronic 28 days: 100mg/kg). This was confirmed by liver, kidney, and brain histopathological changes, as well as hematological and biochemical changes.
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Affiliation(s)
- Azadeh Sabetghadam
- Centre for Drug Research, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
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Fakurazi S, Rahman SA, Hidayat MT, Ithnin H, Moklas MAM, Arulselvan P. The combination of mitragynine and morphine prevents the development of morphine tolerance in mice. Molecules 2013; 18:666-81. [PMID: 23292329 PMCID: PMC6270191 DOI: 10.3390/molecules18010666] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 12/27/2012] [Accepted: 12/28/2012] [Indexed: 12/17/2022] Open
Abstract
Mitragynine (MG) is the major active alkaloid found in Mitragyna speciosa Korth. In the present study, we investigated the enhancement of analgesic action of MG when combined with morphine and the effect of the combination on the development of tolerance towards morphine. Mice were administered intraperitoneally with a dose of MG (15 and 25 mg/kg b.wt) combined with morphine (5 mg/kg b.wt) respectively for 9 days. The antinociceptive effect was evaluated by a hot plate test. The protein expression of cyclic adenosine monophosphate (cAMP) and cAMP response element binding (CREB) was analyzed by immunoblot. Toxicological parameters especially liver and kidney function tests were assessed after the combination treatment with MG and morphine. The concurrent administration of MG and morphine showed significant (p < 0.05) increase in latency time when compared to morphine alone group and the outstanding analgesic effects in the combination regimens were maintained until day 9. For the protein expression, there was a significant increment of cAMP and CREB levels (p < 0.05) in group treated with 5 mg/kg morphine but there was no significant change of these protein expressions when MG was combined with morphine. There was a significant changes in toxicological parameters of various treated groups. The combination treatment of MG and morphine effectively reduce the tolerance due to the chronic administration of morphine.
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Affiliation(s)
- Sharida Fakurazi
- Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; E-Mails: (M.T.H.); (M.A.M.M.)
- Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; E-Mail:
| | - Shamima Abdul Rahman
- Faculty of Pharmacy, Cyberjaya University College of Medical Sciences, 63000 Cyberjaya, Selangor, Malaysia; E-Mail:
| | - Mohamad Taufik Hidayat
- Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; E-Mails: (M.T.H.); (M.A.M.M.)
| | - Hairuszah Ithnin
- Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; E-Mail:
| | - Mohamad Aris Mohd Moklas
- Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; E-Mails: (M.T.H.); (M.A.M.M.)
| | - Palanisamy Arulselvan
- Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; E-Mail:
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Philipp AA, Wissenbach DK, Zoerntlein SW, Klein ON, Kanogsunthornrat J, Maurer HH. Studies on the metabolism of mitragynine, the main alkaloid of the herbal drug Kratom, in rat and human urine using liquid chromatography-linear ion trap mass spectrometry. J Mass Spectrom 2009; 44:1249-1261. [PMID: 19536806 DOI: 10.1002/jms.1607] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Mitragynine (MG) is an indole alkaloid of the Thai medicinal plant Mitragyna speciosa (Kratom in Thai) and reported to have opioid agonistic properties. Because of its stimulant and euphoric effects, Kratom is used as a herbal drug of abuse. The aim of the presented study is to identify the phase I and II metabolites of MG in rat and human urine after solid-phase extraction (SPE) using liquid chromatography-linear ion trap mass spectrometry providing detailed structure information in the MSn mode particularly with high resolution. The seven identified phase I metabolites indicated that MG was metabolized by hydrolysis of the methylester in position 16, O-demethylation of the 9-methoxy group and of the 17-methoxy group, followed, via the intermediate aldehydes, by oxidation to carboxylic acids or reduction to alcohols and combinations of some steps. In rats, four metabolites were additionally conjugated to glucuronides and one to sulfate, but in humans, three metabolites to glucuronides and three to sulfates.
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Affiliation(s)
- Anika A Philipp
- Department of Experimental and Clinical Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Saarland University, D-66421 Homburg (Saar), Germany
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Ranjith NK, Sasikala C, Ramana CV. Rhodethrin: a novel indole terpenoid ether produced by Rhodobacter sphaeroides has cytotoxic and phytohormonal activities. Biotechnol Lett 2007; 29:1399-402. [PMID: 17636389 DOI: 10.1007/s10529-007-9413-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2007] [Revised: 04/16/2007] [Accepted: 04/17/2007] [Indexed: 11/28/2022]
Abstract
A novel metabolite was isolated from the culture supernatants of Rhodobacter sphaeroides OU5 when grown on L-tryptophan as sole source of nitrogen under photoheterotrophic conditions. It was identified by IR, NMR ((1)H, (13)C) and MS as an indole terpenoid ether [3-hydroxy-6-(1H-indol-3-yloxy)-4-methylhexanoic acid] and is named as rhodethrin. Rhodethrin at 0.5 microM gave positive test in auxin bioassay and initiated early rooting in tissue-cultured plants than IAA at 5 microM. Rhodethrin has cytotoxic activity against Sup-T(1) lymphoma and Colo-125 cancer cell lines at 10 nM.
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Affiliation(s)
- N Kumavath Ranjith
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad, 500 046, India
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Di Giorgio C, Lamidi M, Delmas F, Balansard G, Ollivier E. Antileishmanial activity of quinovic acid glycosides and cadambine acid isolated from Nauclea diderrichii. Planta Med 2006; 72:1396-402. [PMID: 17089325 DOI: 10.1055/s-2006-951726] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Nine quinovic acid glycosides and the alkaloid cadambine acid isolated from N. diderrichii, an evergreen endemic plant of West and Central Africa, were assessed for their in vitro antileishmanial activity against Leishmania infantum. Four quinovic acid glycosides and cadambine acid revealed a strong antileishmanial activity (IC (50) = 1 microM) highly specific for the intracellular amastigote form of the parasite. Quinovic acid glycosides were shown to inhibit parasite internalisation by interfering with promastigotes while cadambine acid exerted immunomodulatory activity by inducing NO production in human macrophages. The association of cadambine acid with amphotericin B demonstrated an interesting synergism, suggesting that cadambine acid could be used as a complement of such conventional therapy.
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Affiliation(s)
- Carole Di Giorgio
- Laboratoire de Parasitologie, Hygiène et Zoologie, Faculté de Pharmacie, Marseille, France.
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13
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Horie S, Koyama F, Takayama H, Ishikawa H, Aimi N, Ponglux D, Matsumoto K, Murayama T. Indole alkaloids of a Thai medicinal herb, Mitragyna speciosa, that has opioid agonistic effect in guinea-pig ileum. Planta Med 2005; 71:231-236. [PMID: 15770543 DOI: 10.1055/s-2005-837822] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Recently, we found that mitragynine, a major constituent of Mitragyna speciosa, has an opioid agonistic activity, but its weak potency could not explain the opium-like effect of this plant. In the present study, bioassay-guided fractionation of the crude extract of the leaves of M. speciosa was carried out to search for potent opioid agonists other than mitragynine. Opioid agonistic activities were evaluated using twitch contraction induced by electrical stimulation in guinea-pig ileum. The crude extract of M. speciosa inhibited the twitch contraction in a concentration-dependent manner. The inhibition was reversed by naloxone. The opioid effect was detected only in the crude base fraction, which was followed by the isolation of five indole alkaloids. Among these alkaloids, 7-hydroxymitragynine showed the most potent opioid effect on the electrically-stimulated contraction (pD (2) = 8.38 +/- 0.12). The potency, calculated using pD (2) values, was 30- and 17-fold higher than that of mitragynine and morphine, respectively. Antagonism of naloxone on concentration-response curves for 7-hydroxymitragynine confirmed its opioid effect. These results suggest that the opioid effect of M. speciosa is mostly based on the activity of 7-hydroxymitragynine.
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Affiliation(s)
- Syunji Horie
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan.
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14
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Costa-Campos L, Iwu M, Elisabetsky E. Lack of pro-convulsant activity of the antipsychotic alkaloid alstonine. J Ethnopharmacol 2004; 93:307-310. [PMID: 15234769 DOI: 10.1016/j.jep.2004.03.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2004] [Revised: 02/27/2004] [Accepted: 03/26/2004] [Indexed: 05/24/2023]
Abstract
Psychiatry co-morbidity with epilepsy is common and often requires the combined use of psychotropic and antiepileptic drugs (AEDs). For schizophrenic patients, the occurrence of seizures with atypical agents is highest among antipsychotics, although these agents are more effective in alleviating symptoms (including negative symptoms) and are associated with fewer extrapiramidal effects. The indol alkaloid alstonine is the major component of plants used by traditional Nigerian psychiatrists as anti-dementia drugs. The alkaloid presents an experimental profile very similar to the atypical antipsychotic clozapine. This study aimed to compare the pro-convulsant activity of these two antipsychotic compounds. Through repetitive administration over a 30-day period in a kindling paradigm, it is shown that, unlike clozapine, alstonine does not possess pro-convulsant activity. The data adds to previous suggestions that alstonine deserves to be scrutinized as a model for the development of newer antipsychotics.
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Affiliation(s)
- Luciane Costa-Campos
- UNESC, Departmento de Farmacia, Av. Universitaria 1105, 88806-00 Criciuma, SC, Brazil.
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15
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Matsumoto K, Horie S, Ishikawa H, Takayama H, Aimi N, Ponglux D, Watanabe K. Antinociceptive effect of 7-hydroxymitragynine in mice: Discovery of an orally active opioid analgesic from the Thai medicinal herb Mitragyna speciosa. Life Sci 2004; 74:2143-55. [PMID: 14969718 DOI: 10.1016/j.lfs.2003.09.054] [Citation(s) in RCA: 148] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2003] [Accepted: 09/17/2003] [Indexed: 12/17/2022]
Abstract
Mitragynine is an indole alkaloid isolated from the Thai medicinal plant Mitragyna speciosa. We previously reported the morphine-like action of mitragynine and its related compounds in the in vitro assays. In the present study, we investigated the opioid effects of 7-hydroxymitragynine, which is isolated as its novel constituent, on contraction of isolated ileum, binding of the specific ligands to opioid receptors and nociceptive stimuli in mice. In guinea-pig ileum, 7-hydroxymitragynine inhibited electrically induced contraction through the opioid receptors. Receptor-binding assays revealed that 7-hydroxymitragynine has a higher affinity for micro-opioid receptors relative to the other opioid receptors. Administration of 7-hydroxymitragynine (2.5-10 mg/kg, s.c.) induced dose-dependent antinociceptive effects in tail-flick and hot-plate tests in mice. Its effect was more potent than that of morphine in both tests. When orally administered, 7-hydroxymitragynine (5-10 mg/kg) showed potent antinociceptive activities in tail-flick and hot-plate tests. In contrast, only weak antinociception was observed in the case of oral administration of morphine at a dose of 20 mg/kg. It was found that 7-hydroxymitragynine is a novel opioid agonist that is structurally different from the other opioid agonists, and has potent analgesic activity when orally administered.
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Affiliation(s)
- Kenjiro Matsumoto
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan
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16
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Onunkwo GC. Evaluation of named binders in Rauwolfia vomitoria root tablets. Boll Chim Farm 2000; 139:132-9. [PMID: 10961024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Some physical properties of Rauwolfia vomitoria root tablets were studied. Tablet characteristics studied were: weight uniformity, tensile strength, friability, disintegration time and content uniformity. Tablet property varied depending on the type and concentration of the binder. The tablets had type and concentration of the binder. The tablets had acceptable hardness and friability profiles. Although tablets containing 150 mg R. vomitoria root had lower tensile strength values. All the tablets passed the B.P. disintegration time test of 15 min. Moreover tablets containing 150 mg R. vomitoria root disintegrated under 1 min. at 4% w/w binder concentration.
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Affiliation(s)
- G C Onunkwo
- Department of Pharmaceutical Technology and Industrial Pharmacy-Faculty of Pharmaceutical Sciences-University of Nigeria, Nsukka, Nigeria
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Matsumoto K, Mizowaki M, Suchitra T, Murakami Y, Takayama H, Sakai S, Aimi N, Watanabe H. Central antinociceptive effects of mitragynine in mice: contribution of descending noradrenergic and serotonergic systems. Eur J Pharmacol 1996; 317:75-81. [PMID: 8982722 DOI: 10.1016/s0014-2999(96)00714-5] [Citation(s) in RCA: 138] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Mitragynine is a major alkaloidal constituent of young leaves of Mitragyna speciosa Korth, that is known to exhibit narcotic-like activity. In this study, we investigated the roles of central monoaminergic systems in the antinociceptive action of mitragynine by means of the tail-pinch and hot-plate tests in mice. Mitragynine (1.0-10 micrograms) injected i.c.v. exerted a dose-dependent antinociceptive activity in both tests. The activity of mitragynine (10 micrograms, i.c.v.) in the tail-pinch test was antagonized by reserpine, 6-hydroxydopamine plus nomifensine, and p-chlorophenylalnine treatment, whereas the antinociceptive activity of morphine (3 micrograms) given i.c.v. in this test was attenuated by 6-hydroxydopamine plus nomifensine but not by p-chlorophenylalanine treatment. Moreover, the activity of i.c.v. mitragynine was also antagonized by the alpha 2-adrenoceptor antagonist, idazoxan (10 micrograms), and cyproheptadine (1 microgram) administered intrathecally (i.t.). On the other hand, the antinociceptive action of i.c.v. mitragynine (10 micrograms) in the hot-plate test was abolished by reserpine and 6-hydroxydopamine plus nomifensine, but not by p-chlorophenylalanine treatment. This action was also antagonized by i.t. injection of idazoxan (10 micrograms). These results suggest that both descending noradrenergic and serotonergic systems are involved in the antinociceptive activity of supraspinally administered mitragynine on the mechanical noxious stimulation, while the descending noradrenergic system predominantly contributes to the effect of supraspinal mitragynine on the thermal noxious stimulation. The mechanisms underlying the suppressive action of mitragynine on the nociceptive response may differ from those of morphine in mice.
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Affiliation(s)
- K Matsumoto
- Department of Pharmacology, Research Institute for Wakan-Yaku (Oriental Medicines), Toyama Medical and Pharmaceutical University, Japan
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Matsumoto K, Mizowaki M, Suchitra T, Takayama H, Sakai S, Aimi N, Watanabe H. Antinociceptive action of mitragynine in mice: evidence for the involvement of supraspinal opioid receptors. Life Sci 1996; 59:1149-55. [PMID: 8831802 DOI: 10.1016/0024-3205(96)00432-8] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Mitragynine is a major alkaloidal constituent extracted from the young leaves of Mitragyna speciosa Korth. (Rubiaceae). We investigated an antinociceptive activity of intraperitoneal (i.p.) and intracerebroventricular (i.c.v.) injection of this alkaloid by the tail-pinch and hot-plate tests in mice, and evaluated the mechanisms of the action using naloxone, an opioid receptor antagonist. Mitragynine (5.0-30 mg/kg, i.p. and 1.0-10 micrograms/mouse, i.c.v.) exerted a dose-dependent antinociceptive activity which was maximal at 15-45 min after injection in the tail-pinch and hot-plate tests, but it did not induce a morphine-like behavioral change. the antinociceptive actions of i.p. mitragynine were completely abolished by both s.c. (2 mg/kg) and i.c.v (10 micrograms/mouse) naloxone. The action of i.c.v. mitragynine (10 micrograms/mouse) was also antagonized by i.c.v. naloxone (10 micrograms/mouse). These results indicate that mitragynine itself can induce antinociception by acting in the brain, and that the supraspinal opioid systems are at least partly involved in the antinociceptive action of mitragynine in mice.
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Affiliation(s)
- K Matsumoto
- Division of Pharmacology, Toyama Medical and Pharmaceutical University, Japan
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Affiliation(s)
- K A Swallows
- Department of Chemistry, Oklahoma State University, Stillwater 74078-0447
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Abstract
Alstonine, serpentine and sempervirine, when used at appropriate concentrations cure a relatively important proportion of BALB/C mice inoculated with transplantable YC8 lymphoma ascites cells, as well as Swiss mice bearing Ehrlich ascites carcinoma cells. The development of some solid tumors was only partially prevented. However, when one alkaloid was administered in association with either 5-FU, daunorubicin, 1-(2-chloroethyl) nitrosourea (CCNU) or cyclophosphamide (CP) to mice bearing either ascites carcinoma cells or solid tumors, a high rate of cure was obtained without toxicity. The role of the three alkaloids in the curing of mice and prevention of carcinogenesis is discussed.
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Hirata Y. [Plasma catecholamine concentration in patient's with essential hypertension and its changes by long-term antihypertensive treatment (author's transl)]. Nihon Naika Gakkai Zasshi 1982; 71:438-47. [PMID: 6125549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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22
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Miyamoto K, Wakusawa S, Koshura R. Comination effect of reserpine with antitumor agents in L1210. Gan 1980; 71:408-14. [PMID: 7418986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The antileukemic combined effect of reserpine with 1-gamma-chloropropyl-2-chloromethylpiperidine hydrobromide (CAP-2) and other antitumor agents was studied on mouse leukemia L1210 in comparison with the effects of other Rauwolfia alkaloids and sympatholytic drugs. When reserpine was administered by a single ip injection (2.5 mg/kg) on day 1, the effect of subsequent administration of CAP-2, mitomycin-C, or vinblastine was synergistically enhanced. In this combination with reserpine, the acute lethality of CAP-2 on the host animals was apparently decreased. Among other sympatholytic drugs, rescinnamine, a central nervous system depressant, slightly potentiated the antitumor effect of CAP-2. On the other hand, when reserpine-induced hypothermia was prevented by maintenance of the ambient temperature at 30 degrees, the synergistic combined effect of reserpine was diminished. Chlorpromazine-induced hypothermia did not influence the antitumor effect of CAP-2. It may be concluded that the antileukemic synergism depends partially on the interaction between reserpine and CAP-2 or other antitumor agents in relation to body temperature and/or action on the central nervous system in leukemic mice.
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Smeral R. [Lamuran dragées in the treatment of torpid ulcerations of the leg (author's transl)]. Cesk Dermatol 1979; 54:295-7. [PMID: 527062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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24
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Hugeneck J. [Intravenous infusions in the treatment of arterial occlusive diseases from the surgical point of view]. Wien Med Wochenschr 1976; 126:542-4. [PMID: 788353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Abstract
In an attempt to confirm three reports suggesting a causal link between rauwolfia antihypertensive drugs and female breast carcinoma, all cases of such cancer appearing among the residents of an affluent retirement community were compared with controls chosen from a roster of all women in the same community. Most residents use a single care facility, and patterns of hypertension diagnosis, rauwolfia and other drug use, and medical-care-system patronage were abstracted from medical records. The prevalence of recorded rauwolfia use among the controls were 20 per cent, and that of other drug use was correspondingly high. The risk ratio for rauwolfia use was estimated to be 1.2 (95 per cent confidence interval, 0.7 to 2.2). Risk ratios between 1.0 and 2.0 were also found for other drug use and for measures of care-system patronage. These results do not support the hypothesis that reserpine causes breast cancer.
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Löhr JP, Bartsch GG. [On the absorption and excretion of raubasin in rats with particular reference to a method for the direct determination of the alkaloid]. Arzneimittelforschung 1975; 25:870-3. [PMID: 1174323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A sensitive method has been developed for the determination of raubasin in biological fluids. The procedure involves preliminary solvent extraction of raubasin and its metabolites from alkaline body fluids into chloroform, followed by thin-layer chromatography and in situ fluorimetric quantitation. This method permits the quantitative assay of raubasin down to 0.02 mug with a standard deviation of less than 5%. Drug recovery from plasma is greater than 85%. The method has been applied to the measurement of raubasin concentrations found in rat plasma and urine after a single, oral dose of the alkaloid. A biliary elimination of the unchanged drug and of some metabolites has been demonstrated.
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Gabele A. [Results of treatment of libido disorders in women]. Z Allgemeinmed 1971; 47:666-8. [PMID: 5103322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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29
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Schütz RM, Kramer H. [Reaction of the blood circulation in the extremities with intravenous Raubasin infusions]. Med Welt 1971; 14:554-9. [PMID: 5551941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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30
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Magnin A, Nicod B, Bourquin C, Magnin P. [Pharmacological properties of reserpine 3,5,3'-triiodothyroacetate]. Farmaco Sci 1970; 25:362-85. [PMID: 5451640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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31
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Duncan RJ, Nash CB. Effects of the rauwolfia alkaloids, ajmaline, tetraphyllicine, and serpentine, on myocardial excitability. Arch Int Pharmacodyn Ther 1970; 184:355-61. [PMID: 5453235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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