title: Effects of mitragynine from Mitragyna speciosa Korth leaves on working memory.
abstract: OBJECTIVE
  Mitragyna speciosa Korth from Rubiaceae family is a tropical plant indigenous to Southeast Asia particularly in Thailand, Peninsular of Malaysia and Indonesia. The leaves have been used by natives for their opium-like effect and cocaine-like stimulant ability to combat fatigue and enhance tolerance to hard work. However there is no scientific information about the effect of mitragynine on the cognitive performances. This study is designed to examine the working memory effects of mitragynine which is extracted from Mitragyna speciosa mature leaves.
  
  
  METHODS
  The cognitive effect was studied using object location task and the motor activity in open-field test. Mitragynine 5, 10 and 15 mg/kg and were administered by intraperitoneal (IP) for 28 consecutive days and evaluated on day 28 after the last dose treatment. Scopolamine was used as the control positive drug.
  
  
  RESULTS
  In this study there is prominent effects on horizontal locomotor activity was observed. Mitragynine significantly reduced locomotor activity in open-field test compared with vehicle. In object location task mitragynine (5, 10 and 15 mg/kg) did not showed any significances discrimination between the object that had changed position than the object that had remain in a constant position.
  
  
  CONCLUSIONS
  Our results suggest that chronic administration of mitragynine can altered the cognitive behavioral function in mice.
authors.affiliation: Department of Human Anatomy, Faculty of Medicine and Health Sciences, University Putra Malaysia, Serdang, Selangor, Malaysia.
authors.forename: Evhy
authors.initials: E
authors.lastname: Apryani
authors.forename: M Taufik
authors.initials: MT
authors.lastname: Hidayat
authors.forename: M A A
authors.initials: MA
authors.lastname: Moklas
authors.forename: S
authors.initials: S
authors.lastname: Fakurazi
authors.forename: N Farah
authors.initials: NF
authors.lastname: Idayu
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D007274:Injections, Intraperitoneal; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects*; D051379:Mice; D008813:Mice, Inbred ICR; D032065:Mitragyna / Q000737:chemistry*; D009043:Motor Activity / Q000187:drug effects; D018515:Plant Leaves / Q000737:chemistry; D012601:Scopolamine / Q000494:pharmacology; D046948:Secologanin Tryptamine Alkaloids / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D046948:Secologanin Tryptamine Alkaloids; D012601:Scopolamine; C001801:mitragynine