Analgesic effects of the ethanolic extract from cissus quadrangularis dried stem

Abstract

Cissus quadrangularis Linn. (Phet-Cha-Sung-Khat), a rambling shrub, has been widely used in folk medicine for hemorrhoid treatment. In these studies, we initially determined the analgesic property of a range of the crude extract of C. quadrangularis dried stems (CQ) doses in the mouse hot-plate test. Hot-plate latencies (cut-off 45 sec) were determined in male ICR mice prior to the intraperitoneal (i.p.) administration of 0.9% normal saline solution (NSS), morphine (MO: 10 mg/kg), acetylsalicylic acid (ASA: 150 mg/kg) or various doses of CQ (43.75, 87.5, 175, 350, and 700 mg/kg). Hot-plate latencies were subsequently determined at 15, 30, 45, 60, 90, 120 and 240 min. The mean percent maximum possible effect (%MPE) was calculated and used in the determination of the area of analgesia (%MPE-min). All doses of CQ produced a dose-dependent analgesic response. CQ (175-700 mg/kg) produced analgesic response that was naltrexone-sensitive suggesting opioid-mediated mechanism. In the mouse tail-flick analgesia test, tail-flick latencies (cut-off 4 sec) were determined in male ICR mice prior to the i.p. administration of NSS, MO, ASA or various doses of CQ (43.75-700 mg/kg) and subsequently determined at 7 intervals over a four-hour period. CQ in doses of 87.5 mg/kg and higher produced a significant dose-related analgesic response. Studies then determined the analgesic effect of CQ using the Randall-Selitto analgesia test. Paw-pressure latencies were determined in male Wistar rats prior to i.p. administration of NSS, MO, ASA or various doses of CQ (43.75-700 mg/kg). Paw-pressure latencies were subsequently determined at 15, 30, 45, 60, 90, 120 and 240 min. CQ doses of 175 mg/kg and higher produced a significant dose-related analgesic response. Paw-pressure latencies were also determined in male Wistar rats prior to the i.p. administration of NSS, MO, Indomethacin (5 mg/kg) or various doses of CQ (43.75-700 mg/kg). Carrageenan was then administered into subplantar area of a right hind paw to induce inflammatory response. Withdrawal threshold were determined 2 hours after carrageenan administered on both inflamed and non-inflamed paw. CQ doses of 350 and 700 mg/kg produced significant analgesic responses in the inflamed paw. Taken together these results demonstrate that the crude extract of C. quadrangularis dried stems produced analgesic effect that was dose-dependent in all analgesic testing models and mechanism of action seems to be related to opioid receptor.