lignans has been researched along with Pain* in 16 studies
1 trial(s) available for lignans and Pain
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A clinical study of CPH 82 vs methotrexate in early rheumatoid arthritis.
The objectives of this study were to evaluate the therapeutic efficacy of CPH 82 in comparison with methotrexate (MTX) in adult patients with early, active rheumatoid arthritis (RA) and to compare the tolerance and safety profiles of the two drugs.. The study was a 24-week, double-blind, randomized study in 10 centres of 100 patients with active RA, with a disease duration of less than 2 yr at the start of treatment, which consisted of either CPH 82 300 mg/day or MTX 10 mg/week. The six primary effect variables were: number of swollen joints, Ritchie's articular index, patient's pain score, patient's global score, Health Assessment Questionnaire (HAQ) and C-reactive protein (CRP). Erythrocyte sedimentation rate (ESR), physician's global score and the efficacy according to the European League Against Rheumatism (EULAR) and American College of Rheumatology (ACR) response criteria were also analysed.. There was a significant improvement for both drugs in all variables. Significant differences between the drugs in favour of MTX were found only in patient's pain score, CRP and ESR. By the EULAR criteria, 76% and 86% were judged to be responders in the CPH 82 and MTX groups, respectively. By the ACR criteria, the corresponding figures were 58% and 64%. The most common side-effects were gastrointestinal, which were similar in both groups. The numbers of treatment failures due to adverse events were two with CPH 82 and 14 with MTX.. The clinical effect of CPH 82 in this study was comparable to that of MTX at a dose of 10 mg/week. Both drugs reduced acute-phase reactants, MTX more effectively than CPH 82. The safety profile of CPH 82 was more favourable than that of MTX without folic acid supplementation. Topics: Anti-Inflammatory Agents, Non-Steroidal; Antirheumatic Agents; Arthritis, Rheumatoid; Blood Sedimentation; Double-Blind Method; Female; Glycosides; Humans; Joints; Lignans; Male; Methotrexate; Middle Aged; Pain; Severity of Illness Index; Treatment Outcome | 2000 |
15 other study(ies) available for lignans and Pain
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The Ethanol Extract of Syringa oblata Heartwood, a Mongolian Folk Medicine Containing Major Lignans, Exerts Analgesic and Sedative Effects on Mice.
The heartwood of Syringa oblata Lindl. (SO) is one of Mongolian folk medicines to treat insomnia and pain, while its pharmacological evaluation and underlying mechanism remain unclear. In this study, the sedative effect of ethanol extract of SO (ESO) was evaluated with the locomotor activity test and the threshold dose of pentobarbital sodium-induced sleep test in mice, and the hot plate test, acetic acid-induced writhing test, and formalin test in mice were used to evaluate its analgesic effect. The underlying mechanism of ESO analgesia was explored by RT-PCR and western blot analysis, which is associated with the regulation of the NF-κB signaling pathway. Besides, the main constituents of ESO were characterized by LC/MS data analysis and comparison with isolated pure compounds. The current findings brought evidence for clinical application and further pharmacological and phytochemical studies on SO. Topics: Analgesics; Animals; Ethanol; Hypnotics and Sedatives; Lignans; Medicine, Mongolian Traditional; Mice; Pain; Plant Extracts; Syringa | 2023 |
Chaiqin chengqi decoction ameliorates acute pancreatitis in mice via inhibition of neuron activation-mediated acinar cell SP/NK1R signaling pathways.
Chaiqin chengqi decoction (CQCQD) and its derivatives have been widely used in China for the early management of patients with acute pancreatitis (AP). Numerous studies demonstrate the anti-inflammatory and anti-oxidative effects of CQCQD and derivatives, but whether these effects can be attributed to suppressing neurogenic inflammation, has never been studied.. To investigate the effects of CQCQD on substance P (SP)-neurokinin 1 receptor (NK1R) based neurogenic inflammation in an experimental AP model.. For AP patients on admission, pain score was accessed by visual analog scale (VAS); the levels of serum SP and expressions of pancreatic SP and NK1R were also determined. For in vivo study, mice received 7 intraperitoneal injections of cerulein (50 μg/kg) at hourly intervals to induce AP, whilst controls received normal saline injections. In the treatment groups, CQCQD (10 g/kg, 200 μl) was intragastrically given at the third, fifth, and seventh of the cerulein injection or the NK1R antagonist CP96345 (5 mg/kg) was intraperitoneally injected 30 min before the first cerulein administration. The von Frey test was performed to evaluate pain behavior. Animals were sacrificed at 12 h from the first cerulein/saline injection for severity assessment. Pharmacology network analysis was used to identify active ingredients of CQCQD for AP and pain. In vitro, freshly isolated pancreatic acinar cells were pre-treated with CQCQD (5 mg/ml), CP96345 (1 μM), or selected active compounds of CQCQD (12.5, 25, and 50 μM) for 30 min, followed by SP incubation for another 30 min.. The VAS score as well as the levels of serum SP and expressions of pancreatic SP-NK1R were up-regulated in moderately severe and severe patients compared with those with mild disease. CQCQD, but not CP96345, consistently and significantly ameliorated pain, pancreatic necrosis, and systemic inflammation in cerulein-induced AP as well as inhibited NK1R internalization of pancreatic acinar cells. These effects of CQCQD were associated with reduction of pancreatic SP-NK1R and neuron activity in pancreas, dorsal root ganglia, and spinal cord. Baicalin, emodin, and magnolol, the top 3 active components of CQCQD identified via pharmacology network analysis, suppressed NK1R internalization and NF-κB signal pathway activation in isolated pancreatic acinar cells.. CQCQD ameliorated cerulein-induced AP and its associated pain via inhibiting neuron activation-mediated pancreatic acinar cell SP-NK1R signaling pathways and its active compounds baicalin, emodin, and magnolol contributed to this effect. Topics: Acinar Cells; Analgesics; Animals; Anti-Inflammatory Agents; Biphenyl Compounds; Ceruletide; Drugs, Chinese Herbal; Emodin; Flavonoids; Ganglia, Spinal; Humans; Lignans; Male; Mice, Inbred C57BL; Neurons; Pain; Pancreas; Pancreatitis; Receptors, Neurokinin-1; Signal Transduction; Spinal Cord; Substance P | 2021 |
Antinociceptive Effect of Hinokinin and Kaurenoic Acid Isolated from
Topics: 4-Butyrolactone; Analgesics; Animals; Aristolochia; Benzodioxoles; Chromatography, High Pressure Liquid; Diterpenes; Lignans; Magnetic Resonance Spectroscopy; Male; Mice; Pain; Pain Measurement; Plant Extracts | 2020 |
Suppression of TRPV1 and P2Y nociceptors by honokiol isolated from Magnolia officinalis in 3
Burn pain is one of the worst imaginable pain, associated with considerable morbidity and mortality worldwide. The management of pain made significant progress; however, more research is needed for burn pain. In the present study, the antinociceptive effect of honokiol extracted from Magnolia officinalis was assessed for 3 consecutive days. The third-degree burns were induced by the hot water method. The honokiol both by intraperitoneal (i.p) and intra plantar (i.pl) route and in combination with tramadol (i.p) was found to be effective in significantly reducing the mechanical allodynia, hyperalgesia, thermal hyperalgesia and paw edema. Honokiol also succeeded in reducing weight loss and spontaneous pain behavior in mice. Honokiol treatment both i.p and ipl decrease significantly the loss of total protein (3.3 and 3.4 g/dl of total protein) and albumin (2.2 and 2.6 g/dl of total albumin) respectively. It also significantly recovers the normal balance of blood electrolytes and normalizes blood profile. Effect of honokiol on cytokines and mRNA expression levels of TRPV1 and P2Y were also assessed. Honokiol significantly decreases the expression of TNF-α, IL-1β and IL-6 and decreases expression level of TRPV1 and P2Y. Additionally, TRPV1 and P2Y proteins expression levels were also assessed by Western blot in paw skin tissue, sciatic nerve and spinal cord which were remarkably down-regulated by honokiol. Histological analysis of vehicle control and drug-treated paws were also performed through hematoxylin and eosin (H&E) staining which exhibited that honokiol significantly reduced the dermal layers distortion and inflammation associated with the burn. The antioxidant enzymes and nitric oxide (NO) were also determined through ELISA. Honokiol treatment also potentiates the expression of reduced glutathione and glutathione S-transferase, and catalase levels and reduced significantly the nitric oxide (NO) as compared to the burn-induced group. It can be concluded on the base of the results that honokiol has a significant analgesic activity through its action on cytokines and by downregulating TRPV1 and P2Y receptors. It also has a protective role against burn damage by upregulation of antioxidants. Topics: Analgesics; Animals; Biphenyl Compounds; Burns; Cytokines; Edema; Hyperalgesia; Inflammation; Inflammation Mediators; Interleukin-1beta; Lignans; Magnolia; Male; Mice; Mice, Inbred BALB C; Pain; Receptors, Purinergic P2Y; Signal Transduction; Spinal Cord; TRPV Cation Channels; Tumor Necrosis Factor-alpha; Up-Regulation | 2019 |
Isolation of a dihydrobenzofuran lignan, icariside E4, with an antinociceptive effect from Tabebuia roseo-alba (Ridley) Sandwith (Bignoniaceae) bark.
The antinociceptive activity of icariside E4, a dihydrobenzofuran-type lignan isolated from Tabebuia roseo-alba (Ridley) Sandwith (Bignoniaceae) bark, was evaluated in mice by using chemical and thermal models of nociception. Intraperitoneal (i.p.) administration of crude T. roseo-alba bark extract and its methanol fraction inhibited acetic acid-induced abdominal constriction in mice. Furthermore, i.p. administration of 0.1, 1, and 10 mg/kg of icariside E4 reduced the number of writhes evoked by acetic acid injection by 46.9, 82.3, and 66.6%, respectively. Icariside E4 administration had no effect in the first phase of the formalin test, but it reduced nociceptive behavior in the second phase as indicated by a reduction in the licking time. Icariside E4 did not modify thermal nociception in the hot-plate test model, suggesting that it had a peripheral antinociceptive action. The antinociceptive effect of icariside E4 in the writhing test was reversed by pre-administration of glibenclamide, but not of naloxone, atropine, yohimbine, or haloperidol. Together, these results indicated that the antinociceptive activity of icariside E4 from T. roseo-alba in models of chemical pain occurred through ATP-sensitive K(+) channel-dependent mechanisms. Topics: Acetic Acid; Analgesics; Animals; Behavior, Animal; Dose-Response Relationship, Drug; Formaldehyde; Glycosides; Hot Temperature; Injections, Intraperitoneal; KATP Channels; Lignans; Male; Mice; Pain; Pain Measurement; Plant Bark; Plant Extracts; Tabebuia | 2015 |
Pain Modulation by Lignans (Phyllanthin and Hypophyllanthin) and Tannin (Corilagin) Rich Extracts of Phyllanthus amarus in Carrageenan-induced Thermal and Mechanical Chronic Muscle Hyperalgesia.
The current study was aimed at evaluating the antihyperalgesic effects of lignans (phyllanthin and hypophyllanthin) and tannin (corilagin) rich three standardized extracts of Phyllanthus amarus in a model of chronic musculoskeletal inflammatory pain. Three percent carrageenan injected in the gastrocnemius muscle produced hyperalgesia to mechanical and heat stimuli ipsilaterally, which spreads to the contralateral side within 7 to 9 days. To investigate the effects on chronic thermal and mechanical hypersensitivity, three extracts of P. amarus in three doses (100, 200, and 400 mg/kg) were administered to animals intraperitoneally from 14th day to 22nd day after intramuscular injection of carrageenan. It was observed that intraperitoneal administrations of Phyllanthus extracts showed antihyperalgesic activity, as they elevated thermal and mechanical threshold, which was supported by histopathological observations along with reduction in prostaglandin E2 (PGE2) concentration. In conclusion, we strongly suggest that the observed antihyperalgesic and antiinflammatory effects of P. amarus in current pain model are mediated via spinal or supraspinal neuronal mechanisms, mainly by inhibition of PGE2. Modulation of chronic muscular inflammation may be due to presence of phytoconstituents like phyllanthin, hypophyllanthin, and corilagin, which offers a promising means for treatment of chronic muscle pain. Topics: Animals; Carrageenan; Dinoprostone; Disease Models, Animal; Glucosides; Hydrolyzable Tannins; Hyperalgesia; Inflammation; Lignans; Male; Muscle, Skeletal; Musculoskeletal Pain; Pain; Phyllanthus; Rats, Wistar | 2015 |
Honokiol for the Treatment of Neonatal Pain and Prevention of Consequent Neurobehavioral Disorders.
This study examined the short- and long-term neuroprotective and analgesic activity of honokiol (a naturally occurring lignan isolated from Magnolia) on developing brains in neonates exposed to inflammatory pain, known to cause neuronal cell death. Postnatal day 4 (P4) neonatal rat pups were subjected to intraplantar formalin injection to four paws as a model of severe neonatal pain. Intraperitoneal honokiol (10 mg/kg) or corn oil vehicle control was administered 1 h prior to formalin insult, and animals were maintained on honokiol through postnatal day 21 (P21). Behavioral tests for stress and pain were performed after the painful insult, followed by morphological examinations of the brain sections at P7 and P21. Honokiol significantly attenuated acute pain responses 30 min following formalin insult and decreased chronic thermal hyperalgesia later in life. Honokiol-treated rats performed better on tests of exploratory behavior and performed significantly better in tests of memory. Honokiol treatment normalized hippocampal and thalamic c-Fos and hippocampal alveus substance P receptor expression relative to controls at P21. Together, these findings support that (1) neonatal pain experiences predispose rats to the development of chronic behavioral changes and (2) honokiol prevents and reduces both acute and chronic pathological pain-induced deteriorations in neonatal rats. Topics: Analgesics; Animals; Biphenyl Compounds; Formaldehyde; Lignans; Magnolia; Male; Molecular Structure; Neuroprotective Agents; Pain; Rats | 2015 |
Antinociceptive and anti-inflammatory activities of the sesame oil and sesamin.
Sesame oil is widely consumed as nutritious food, cooking oil, and in pharmaceuticals and food. In this study, the antinociceptive and anti-inflammatory properties of the sesame oil and sesamin were investigated. The sesame oil and sesamin reduced the number of abdominal contortions at the doses 100, 200, or 400 mg/kg. The first and second phases of the time paw licking were inhibited by sesame oil and sesamin (100, 200, or 400 mg/kg). After 90 min of treatment, sesame oil and sesamin increased the reaction time on a hot plate (200 or 400 mg/kg). Considering the tail-immersion assay, the sesame oil and sesamin produced significant effect after 60 min at the doses of 100, 200, or 400 mg/kg. After 4 h of application of the carrageenan, the sesame oil and sesamin were effective against the paw edema. The exudate volume and leucocyte migration were also reduced by sesame oil and sesamin. These results suggest that sesamin is one of the active compounds found in sesame oil and justify the antinociceptive and anti-inflammatory properties of this product. Topics: Acetic Acid; Analgesics; Animals; Anti-Inflammatory Agents; Carrageenan; Dioxoles; Edema; Formaldehyde; Inflammation; Lignans; Male; Mice; Nociception; Pain; Pleurisy; Rats; Rats, Wistar; Sesame Oil; Toxicity Tests, Acute | 2014 |
Antinociceptive and anti-inflammatory activities of ethyl acetate fraction from Zanthoxylum armatum in mice.
Zanthoxylum armatum DC. is a traditional Chinese medicine that is prescribed to alleviate pain and treat inflammatory disorders. This species is distributed mainly in the southeast and southwest regions of China. In the present study, we found that ethyl acetate fraction of ethanolic extract of Z. armatum could significantly decrease acetic acid-induced writhing numbers, and suppress formalin induced licking times in the first phase at the highest dose and in the second phase at all tested doses. This observation revealed that Z. armatum extract possessed powerful antinociceptive activity. The mechanisms of the antinociceptive effect might be mainly involved in the periphery inflammatory analgesic. In addition, the ethyl acetate fraction also inhibited xylene-induced ear swelling in a dose-dependent manner in mice. Eight lignans [eudesmin, horsfieldin, fargesin, kobusin, sesamin, asarinin, planispine A, and pinoresinol-di-3,3-dimethylallyl] were identified as major components of the ethyl acetate fraction. Considering related studies reporting the anti-inflammatory activity for the identified lignans, lignan might be responsible for its anti-inflammatory activity. Our results confirm that the traditional use of Z. armatum in the treatment of inflammation and pain is warranted. Topics: Acetic Acid; Analgesics; Animals; Anti-Inflammatory Agents; Behavior, Animal; Dose-Response Relationship, Drug; Ear; Edema; Formaldehyde; Inflammation; Lignans; Mice; Pain; Phytotherapy; Plant Extracts; Plant Roots; Plant Stems; Zanthoxylum | 2011 |
Antinociceptive and antiinflammatory activities of grandisin extracted from Virola surinamensis.
The antinociceptive and antiinflammatory properties of the neolignan, grandisin, isolated from Virola surinamensis (Myristicaceae) were investigated. Grandisin (GRA) is present in several plant species from Brazil used in popular medicine for the treatment of disorders such as colic, inflammation, rheumatism, dyspepsia and liver dysfunction. These studies demonstrated that GRA is able to inhibit the acetic acid-induced writhing in mice dose-dependently, and that this effect is not caused by motor incoordination or sedation due to depressant effect in the CNS. Through the formalin test the antiinflammatory activity of GRA was characterized, this substance reduced the time licking the paw by 60.5% (only in the second phase (inflammatory pain). This activity was also verified by the oil-induced ear oedema test, where GRA 10.0 mg/kg reduced the oedema by 36.4%. The results suggest that GRA has antinociceptive effects arising from antiinflammatory activity. Topics: Analgesics; Animals; Anti-Inflammatory Agents; Dose-Response Relationship, Drug; Furans; Lignans; Male; Mice; Myristicaceae; Pain; Pain Measurement; Plant Extracts | 2010 |
Analgesic activity of affinin, an alkamide from Heliopsis longipes (Compositae).
Heliopsis longipes (Compositae) is a Mexican plant used as analgesic in pain toothache. A solution of 10mug/ml of dichloromethane extract from this plant showed analgesic activity determined by means of GABA release in mice brain slices. Through a bioassay-directed separation, fractions G-1, G-2, G-4 and G-6 at the same concentration were active. Affinin was the unique and common active compound, and evoke the GABA release 0.5min after administration at 1x10(-4)M concentration. Inactive compound were undeca-2E-en-8,10-dyinoic acid isobutylamide, hinokinin, 2'-hydroxyhinokinin, 3beta-sn-glyceroyl-(1''-palmitoxy)urs-12-ene, 13(18)-ursen-3beta-ol, 13(18)-ursen-3beta-acetate, beta-sitosterol and stigmasterol. The analgesic activity of Heliopsis longipes could be associated to affinin. Topics: 4-Butyrolactone; Alkenes; Amides; Analgesics; Animals; Asteraceae; Benzodioxoles; Brain; Dioxoles; Female; gamma-Aminobutyric Acid; In Vitro Techniques; Lignans; Medicine, Traditional; Methylene Chloride; Mexico; Mice; Pain; Plant Extracts; Plants, Medicinal; Polyunsaturated Alkamides | 2007 |
Anti-inflammatory and analgesic activities of the ethanolic extracts from Zanthoxylum riedelianum (Rutaceae) leaves and stem bark.
We have evaluated the anti-inflammatory and analgesic properties of the leaves (LCE) and stem bark (BCE) crude extracts of Zanthoxylum riedelianum (Rutaceae). Different fractions of the stem bark extract (hexane, BCEH; dichloromethane, BCED; ethyl acetate, BCEE; and lyophilized aqueous residual, BCEW) were also investigated. We studied the effects of the extracts and fractions using the rat paw oedema test induced by carrageenan, dextran, histamine or nystatin; the mouse abdominal constriction test; the mouse hot-plate test (only for LCE and BCE); and the mouse formalin test. Both extracts and all BCE fractions displayed anti-inflammatory activity in the carrageenan-induced oedema model, but not for dextran, histamine or nystatin. Considering the analgesic models, both extracts showed antinociceptive activity, but BCE was more active than LCE in models of central pain. All BCE fractions showed significant inhibition in the abdominal constriction test and in both phases of the formalin test. When BCED was submitted to phytochemical procedures it led to the isolation of six lignans (sesamin, methylpluviatolide, dimethylmatairesinol, piperitol-4(')-O-(gamma),(gamma)-dimethylallyl ether, kaerophyllin and hinokinin), and a triterpene (lupeol). Inhibition of cyclooxygenase and its metabolites may have been involved in the mechanism of action of this plant, considering previous studies reporting the anti-inflammatory and analgesic activity for the identified lignans, as well as anti-inflammatory activity for lupeol. Topics: Analgesics; Animals; Anti-Inflammatory Agents; Disease Models, Animal; Dose-Response Relationship, Drug; Edema; Inflammation; Lignans; Male; Mice; Pain; Pain Measurement; Pentacyclic Triterpenes; Plant Bark; Plant Extracts; Plant Leaves; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Wistar; Triterpenes; Zanthoxylum | 2007 |
Effects of honokiol and magnolol on acute and inflammatory pain models in mice.
The antinociceptive actions of honokiol and magnolol, two major bioactive constituents of the bark of Magnolia officinalis, were evaluated using tail-flick, hot-plate and formalin tests in mice. The effects of honokiol and magnolol on the formalin-induced c-Fos expression in the spinal cord dorsal horn as well as motor coordination and cognitive function were examined. Data showed that honokiol and magnolol did not produce analgesia in tail-flick, hot-plate paw-shaking and neurogenic phase of the overt nociception induced by intraplantar injection of formalin. However, honokiol and magnolol reduced the inflammatory phase of formalin-induced licking response. Consistently, honokiol and magnolol significantly decreased formalin-induced c-Fos protein expression in superficial (I-II) laminae of the L4-L5 lumbar dorsal horn. However, honokiol and magnolol did not elicit motor incoordination and memory dysfunction at doses higher than the analgesic dose. These results demonstrate that honokiol and magnolol effectively alleviate the formalin-induced inflammatory pain without motor and cognitive side effects, suggesting their therapeutic potential in the treatment of inflammatory pain. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Biphenyl Compounds; Central Nervous System Depressants; Disease Models, Animal; Drug Evaluation, Preclinical; Fixatives; Formaldehyde; Inflammation; Lignans; Lumbosacral Region; Magnolia; Memory; Mice; Pain; Posterior Horn Cells; Proto-Oncogene Proteins c-fos | 2007 |
Analgesic and anti-inflammatory activities evaluation of (-)-O-acetyl, (-)-O-methyl, (-)-O-dimethylethylamine cubebin and their preparation from (-)-cubebin.
The anti-inflammatory and antinociceptive effects of the acetylated (2), methylated (3) and aminated (4) derivatives of cubebin (1), obtained by its reaction with acetic anhydride, methyl iodide and dimethylethylamine chloride, respectively, were investigated, using different animal models. The compound (2) was the most effective anti-inflammatory one in the carrageenin-induced paw edema in rats and was the only one which showed dose-response correlation for this assay with r = 0.993 and Y = 64.58x + 0.22. Besides, compounds (2) and (4) were more effective than cubebin in inhibiting acetic acid-induced writhing in mice, producing dose-response correlation with doses of 10, 20 and 30 mg/kg, respectively. Regarding the hot plate and the cell migration tests in rats, none of the four tested compounds showed activity. Overall, the results showed that the acetylation and amination of cubebin were efficient in enhancing its analgesic activity, as well as its anti-inflammatory activity. Topics: Acetic Acid; Analgesics; Animals; Anti-Inflammatory Agents, Non-Steroidal; Carrageenan; Dioxoles; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Furans; Lignans; Male; Mice; Pain; Pain Measurement; Rats; Rats, Wistar | 2004 |
Anti-allodynic and anti-oedematogenic properties of the extract and lignans from Phyllanthus amarus in models of persistent inflammatory and neuropathic pain.
This study investigated the anti-allodynic and anti-oedematogenic effects of the hexanic extract, lignan-rich fraction and purified lignans from a plant used in the traditional medicine, Phyllanthus amarus, in the inflammatory and neuropathic models of nociception. The hexanic extract inhibited the allodynia and the oedema induced by the intraplantar injection of complete Freund's adjuvant (CFA). The inhibition observed was 76 +/- 7% (ipsilateral paw), 64 +/- 7% (contralateral paw), and 41 +/- 2% (oedema). Otherwise, the lignan-rich fraction or the pure lignans did not affect CFA-induced allodynia. Administered chronically, the lignan fraction reduced CFA-induced paw oedema (39 +/- 9%). When evaluated in the model of neuropathic pain caused by partial ligation of sciatic nerve, the hexanic extract inhibited the mechanical allodynia (77 +/- 7%), with a similar efficacy to the gabapentin (71 +/- 10%). The anti-allodynic effects of hexanic extract of P. amarus seem not to be associated with the impairment of motor co-ordination or with the development of tolerance. Finally, the treatment with hexanic extract inhibited the increase of myeloperoxidase activity, either following intraplantar injection of CFA or after sciatic nerve injury. It is concluded that, apart from its anti-inflammatory actions, which are probably linked to the presence of lignans, another as yet unidentified active principle(s) present in the hexanic extract of P. amarus produces pronounced anti-allodynia in two models of inflammatory and neuropathic pain. Considering that few drugs are currently available for the treatment of chronic pain, especially of the neuropathic type, the present results may have clinical relevance and open new possibilities for the development of new anti-allodynic drugs. Topics: Acetates; Amines; Analgesics; Animals; Anti-Inflammatory Agents; Cyclohexanecarboxylic Acids; Edema; Enzyme Inhibitors; Excitatory Amino Acid Antagonists; Freund's Adjuvant; Gabapentin; gamma-Aminobutyric Acid; Hexanes; Inflammation; Ligation; Lignans; Male; Mice; Motor Activity; Neutrophil Infiltration; Pain; Peripheral Nervous System Diseases; Peroxidase; Phyllanthus; Physical Stimulation; Plant Extracts; Psychomotor Performance; Sciatica; Solvents | 2003 |