Analgesic Effect of the Herbal Medicine Catuama in Thermal and Chemical Models of Nociception in Mice

Abstract

The antinociceptive effect of the herbal medicine Catuama and the hydroalcoholic extract (HE) of each plant present in this extract were investigated in chemical and thermal models of nociception in mice. The extract of Catuama (200 mg/kg, p.o.) caused time‐dependent and long‐lasting antinociception against acetic acid‐induced writhing, formalin and capsaicin‐induced licking and also in the tail‐flick and hot‐plate assays. Its maximal analgesic effect was reached 6 h after its oral administration and this effect lasted for at least 12 h. When given 6 h prior to testing (100 and 200 mg/kg, p.o.), the extract elicited dose‐related antinociception, but at 400 mg/kg, its analgesic effect was greatly reduced. The antinociception caused by the extract of Catauma, like those produced by morphine, was largely antagonized by naloxone. The daily administration of the extract (200 mg/kg, p.o. for 4 days) or morphine (5 mg/kg, s.c. for 4 days) produced progressive tolerance, an effect which was reverted by naloxone (5 mg/kg, i.p.). In addition, the Catuama extract showed cross‐tolerance with morphine. The Catuama antinociception was not due to its non‐specific effects such as muscle relaxation or sedation of animals, nor was it secondary to its antiinflammatory property. When analysed separately the hydroalcoholic extract (HE) obtained from Trichilia catigua, Paullinia cupana, Ptychopelatum olacoids, Zinziber officinalis (200 mg/kg, p.o., 6 h prior) all inhibited acetic acid‐induced pain (82%±2%; 66%±2%; 42%±2% and 30%±4% of inhibition, respectively (p<0.01). In the formalin test the HE of P. olacoids; P. cupana; T. catigua and to a lesser extent, Z. officinalis (200 mg/kg, p.o., 6 h prior) also inhibited both phases of formalin‐induced pain (p<0.01). Thus, antinociception caused by the Catuama extract seems to be dependent on the interaction of the several active principles present in these plants. The mechanisms underlying the antinociception caused by extract of herbal medicine Catuama is still not completely understood, but a significant number of these effects are related to its interaction with the naloxone sensitive opioid system. Together, the results indicate that the herbal medicine Catuama may constitute a useful therapeutic agent for the treatment of clinical pain. © 1997 by John Wiley & Sons, Ltd.

Antinociceptive Activity ofTrichilia catiguaHydroalcoholic Extract: New Evidence on Its Dopaminergic Effects

“…In our study, T. catigua extract produced marked, time-related and long-lasting antinociceptive effect in the hot-plate model. This result is in accordance with the previous one found by Vaz et al [ 3 ], showing that Catuama effects started to decrease after 6 h. In this test, the antinociceptive activities of T. catigua are probably mediated by the dopaminergic system, and to a lesser extent, the opioid one. This conclusion is based on data showing that dopamine D 1 receptor antagonist SCH23390 completely inhibited the extract antinociceptive effect in the hot-plate test, whilst the opioid antagonist naloxone prevented it only partially.…”

Anti-nociceptive effects of Carpolobia lutea G. Don (Polygalaceae) leaf fractions in animal models

“…The hot-plate test is commonly used for assays of narcotic analgesics (Vaz et al 1997). The results suggest that CL ethyl acetate fraction demonstrate a central analgesic effect, as evidenced by the increase in the reaction time of mice in the hot-plate test.…”

Analgesic and anti-inflammatory effects of Ligularia fischeri leaves in experimental animals

“…Animals treated with the LF (100 and 200 mg/kg) in the hot-plate test presented a longer latency time than the control group, with the dose of 200 mg/kg provoking the longest latency. The hot-plate test is commonly used for assays of narcotic analgesics (Vaz et al, 1997). The results suggest that LF has a central analgesic effect, as evidenced by the increase in reaction time of mice in the hot-plate test.…”