title: Antinociceptive activity of petroleum ether fraction from the MeOH extracts of Paederia scandens in mice.
abstract: The petroleum ether fraction of MeOH extract from Paederia scandens was evaluated on anti-nociceptive activity in mice using chemical and thermal models of nociception. Given orally, the petroleum ether fraction (PEF) at doses of 20, 40 and 80mg/kg produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid and subplantar formalin or capsaicin injections and on thermal nociception in the tail-flick test and in the hot plate test. More significant inhibition of nociception was observed at dose of 80mg/kg of the petroleum ether fraction. In the pentobarbital sodium-induced sleeping time test and the open-field test, the petroleum ether fraction neither significantly enhanced the pentobarbital sodium-induced sleeping time nor impaired the motor performance, indicating that the observed anti-nociception was unlikely due to sedation or motor abnormality. Moreover, the petroleum ether fraction-induced anti-nociception in both capsaicin and formalin tests was insensitive to naloxone, but was significantly antagonized by glibenclamide. These results suggested that the petroleum ether fraction produced anti-nociception possibly related to glibenclamide-sensitive K(+)-ATP channels, which merited further studies regarding the precise site and mechanism of action. The major constituents of the petroleum ether fraction (PEF) determined by GC/MS analysis, are linoleic acid, the sterols and vitamin E. Therefore it can be suggested that they exert synergetic effects and are together responsible for the antinociceptive activity of the PEF-fraction.
authors.affiliation: Department of Pharmacognosy, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, PR China.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Chen
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.forename: Yu-Liang
authors.initials: YL
authors.lastname: Jiao
authors.forename: Peng
authors.initials: P
authors.lastname: Wei
authors.forename: Qiao-Yan
authors.initials: QY
authors.lastname: Zhang
authors.forename: Khalid
authors.initials: K
authors.lastname: Rahman
authors.forename: Han-Chen
authors.initials: HC
authors.lastname: Zheng
authors.forename: Lu-Ping
authors.initials: LP
authors.lastname: Qin
mesh_terms: D019342:Acetic Acid; D000473:Alkanes; D000700:Analgesics / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D002211:Capsaicin; D005557:Formaldehyde; D006358:Hot Temperature; D000432:Methanol; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity / Q000187:drug effects; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy*; D010424:Pentobarbital; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D019666:Rubiaceae / Q000737:chemistry*; D012890:Sleep / Q000187:drug effects
chemical_list: D000473:Alkanes; D000700:Analgesics; D010936:Plant Extracts; D005557:Formaldehyde; D010424:Pentobarbital; C004544:naphtha; D019342:Acetic Acid; D002211:Capsaicin; D000432:Methanol