title: Antinociceptive and antidepressant-like effects of the crude extract of Vitex megapotamica in rats.
abstract: BACKGROUND
  Vitex megapotamica (Spreng) Moldenke has been used in South American folk medicine to treat inflammatory diseases. However, the effects of V. megapotamica on animal models of nociception and depression have not been evaluated.
  
  
  OBJECTIVE
  This study investigated whether the crude leaf extract of V. megapotamica exhibits antinociceptive and antidepressant-like effects in a Freund's adjuvant-induced chronic inflammation and depression model.
  
  
  METHODS
  Chronic inflammation was induced in rats by the intraplantar administration of complete Freund's adjuvant (CFA; 100μl). The effect of oral crude extract of V. megapotamica (VmE; 3-30mg/kg, p.o.) on nociception (thermal hyperalgesia, mechanical allodynia and arthritis score), inflammation (edema, myeloperoxidase activity), immobility (forced swimming test), locomotor activity (open field), gastrointestinal transit, hyperalgesia and naloxone-precipitated morphine withdrawal syndrome was evaluated. Naloxone (0.4mg/kg, i.p.) was used to investigate the involvement of opioid system in the currently described effects of VmE.
  
  
  RESULTS
  Crude extract caused antinociceptive/antidepressant-like effects in the CFA-induced chronic inflammation model, which was prevented by naloxone. The VmE extract (10mg/kg, p.o.) did not alter the locomotor activity, gastrointestinal function and inflammatory parameters and did not cause hyperalgesia.
  
  
  CONCLUSIONS
  V. megapotamica induces opioid-dependent antinociception and antidepressant-like effect, without anti-inflammatory activity. The results support the use of VmE as analgesic and antidepressant.
authors.affiliation: Graduate Program in Biological Sciences: Toxicological Biochemistry, Center of Natural and Exact Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Fernanda Regina
authors.initials: FR
authors.lastname: Hamann
authors.affiliation: Pharmacy Undergraduation Program, Centro Universitário Franciscano - UNIFRA, Santa Maria, RS, Brazil.
authors.forename: Adriana Maria
authors.initials: AM
authors.lastname: Zago
authors.affiliation: Center of Innovation and Pre-clinical Pharmacology - CIEnP, Florianopolis, SC, Brazil.
authors.forename: Mateus Fortes
authors.initials: MF
authors.lastname: Rossato
authors.affiliation: Graduate Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Veronica Rubert
authors.initials: VR
authors.lastname: Beck
authors.affiliation: Graduate Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Carlos Fernando
authors.initials: CF
authors.lastname: Mello
authors.affiliation: Graduate Program in Pharmaceutical Sciences, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Thiele Faccim
authors.initials: TF
authors.lastname: de Brum
authors.affiliation: Graduate Program in Chemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Leandro Machado
authors.initials: LM
authors.lastname: de Carvalho
authors.affiliation: Graduate Program in Chemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Henrique
authors.initials: H
authors.lastname: Faccin
authors.affiliation: Graduate Program in Biological Sciences: Toxicological Biochemistry, Center of Natural and Exact Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil. Electronic address: saramarchesan@hotmail.com.
authors.forename: Sara Marchesan
authors.initials: SM
authors.lastname: Oliveira
authors.affiliation: Graduate Program in Biological Sciences: Toxicological Biochemistry, Center of Natural and Exact Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil; Graduate Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil. Electronic address: maribel.rubin@gmail.com.
authors.forename: Maribel Antonello
authors.initials: MA
authors.lastname: Rubin
mesh_terms: D000284:Administration, Oral; D000700:Analgesics / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000928:Antidepressive Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects*; D003863:Depression / Q000209:etiology / Q000517:prevention & control* / Q000523:psychology; D004195:Disease Models, Animal; D005620:Freund's Adjuvant; D006930:Hyperalgesia / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D007249:Inflammation / Q000139:chemically induced; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D059225:Nociception / Q000187:drug effects*; D017288:Pain Threshold / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D013550:Swimming; D013997:Time Factors; D020950:Vitex / Q000737:chemistry*
chemical_list: D000700:Analgesics; D000928:Antidepressive Agents; D009292:Narcotic Antagonists; D010936:Plant Extracts; D009270:Naloxone; D005620:Freund's Adjuvant
keywords: Allodynia; Forced swimming test; Hyperalgesia; Opioid; Tarumã; Verbenaceae