Antinociceptive and anti-inflammatory effects of stachytarpheta jamaicensis (L.) Vahl (Verbenaceae)in experimental animal models

• Main Authors: Azam Shah, T.M (Author), Chiong, H.S (Author), Israf, D.A (Author), Lai, S.K (Author), Sulaiman, M.R (Author), Zakaria, Z.A (Author)
• Format: Article
• Language: English
• Subjects: acetic acid; acetylsalicylic acid; Analgesics; animal experiment; animal model; animal tissue; Animals; antiinflammatory activity; Anti-inflammatory activity; Anti-Inflammatory Agents; antinociception; Antinociceptive activity; article; Aspirin; carrageenan; controlled study; dose response; drug dose comparison; drug mechanism; experimental test; formaldehyde; granuloma; hot plate test; male; Male; medicinal plant; Mice; Mice, Inbred BALB C; morphine; Morphine; mouse; naloxone; nonhuman; opiate receptor; Opioid mechanism; Pain Measurement; paw edema; paw licking test; Phytotherapy; plant extract; Plant Extracts; Plant Leaves; rat; Rats; Rats, Sprague-Dawley; Stachytarpheta jamaicensis; Stachytarpheta jamaicensis extract; unclassified drug; Verbenaceae; writhing test
• Online Access: View Fulltext in Publisher; View in Scopus

 Objective: The present study was carried out to explore the antinociceptive as well as the anti-inflammatory effects of an ethanol extract of Stachytarpheta jamaicensis (L.) Vahl (EESJ) using 3 models of nociception and 2 models of inflammation in experimental animals. Materials and Methods: EESJ was prepared by overnight soaking of the oven-dried (50°C; 72 h) ground leaves (500 g) in 80% ethanol (1:5; w/v). The filtrate was evaporated to dryness (50°C), resuspended in distilled water at concentrations to provide the desired doses of 50, 100 and 150 mg/kg. For antinociceptive effects, 3 models were used: acetic acid-induced abdominal writhing, hot-plate- and formalin-induced paw-licking tests; for anti-inflammatory effects, 2 models were used - carrageenan-induced paw edema and cotton-pellet-induced granuloma tests. Appropriate doses were administered intraperitoneally (i.p.) to mice/rats prior to each test. The mechanisms of antinociceptive action of the extract were also investigated by pretreatment with naloxone (5 mg/kg, i.p.). Results: The extract exhibited significant (p < 0.05) antinociceptive activity in all nociceptive models tested with dose-dependent activity observed using the abdominal writhing and formalin tests. Pretreatment with naloxone partially, but significantly (p < 0.05) reversed the antinociceptive activity of the extract when assessed using the abdominal-writhing- and formalin-induced paw-licking tests, and completely inhibited its activity when the hot-plate test was used. The extract also showed significant (p < 0.05) anti-inflammatory activity in both the acute (carrageenan-induced paw edema test) and the chronic (cotton-pellet granuloma test) tests. Conclusion: This study showed the potential of EESJ to exert antinociceptive and anti-inflammatory activities, the former being modulated via peripheral and central mechanisms and involving, in part, activation of the opioid receptor system. Copyright © 2009 S. Karger AG, Basel.