en Artificial intelligence Original Research: Basic Science in Medicine Original Research: Basic Science in Medicine The antinociceptive effect of Elaeagnus angustifolia fruits was studied in mice. The antinociceptive effect of ethanolic and boiling water extracts was studied using two thermal stimuli, the hot-plate and tail-flick tests. The intraperitoneal and oral administration of the ethanolic extract of seed 0.75-7.00 g/kg), but not pericarp and medulla had significant antinociceptive activity in the hot-plate test. Naloxone pretreatment did not inhibit the antinociceptive activity of the extract. The aqueous extract of different parts of the fruit (seed, medulla and pericarp) had antinociceptive activity in this test. The ethanolic extract of the seed had no antinociceptive effect in the tail-flick test and its effect was not abolished by naloxone. A 70% failure rate in the traction test (a muscle relaxation test) was induced by ethanolic extract of the seed (3.5 g/kg), compared with the 75% induced by the reference drug diazepam (2.5 mg/kg). It is concluded that the antinociceptive effect of E. angustifolia may be mediated by a supraspinal effect and muscle relaxation activity. Elaeagnus angustifolia; Antinociceptive activity; Muscle relaxation, Hot-plate, Tail-flick, Traction test, Medicinal plants. 77 81 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-298-357&slc_lang=en&sid=1 HOSSEIN HOSSEINZADEH 20031947532846004509 20031947532846004509 Yes From the Faculty of Pharmacy, Mashhad University of Medical Sciences, P.O. Box 91775-1365, Mashhad, IR.Iran. MOHAMMAD REZA TAHERI 20031947532846004510 20031947532846004510 No