Evaluation of the orofacial antinociceptive profile of the ethyl acetate fraction and its major constituent, rosmarinic acid, from the leaves of Hyptis pectinata on rodents

ABSTRACT Hyptis pectinata (L.) Poit., Lamiaceae, popularly known as "sambacaitá," is an aromatic shrub largely grown in the Brazilian northeastern. We investigated the antinociceptive effects of the ethyl acetate fraction obtained from the leaves of H. pectinata and of its main constituent rosmarinic acid, on formalin (2%)-, glutamate (25 µM)- and capsaicin (2.5 µg)-induced orofacial nociception in rodents. Male mice were pretreated with ethyl acetate fraction (100, 200 or 400 mg/kg, p.o.), rosmarinic acid (10 or 20 mg/kg, p.o.), morphine (5 mg/kg, i.p.), or vehicle (distilled water + 0.2% Tween 80). Ethyl acetate fraction reduced the nociceptive face-rubbing behavior during the two phase of the formalin test, whereas pretreatment with rosmarinic acid decreased the pain behavior in the second phase. Ethyl acetate fraction produced significant antinociceptive effects in the capsaicin and glutamate tests. This study showed that oral administration of ethyl acetate fraction produced potent antinociceptive effects compared to treatment with rosmarinic acid.

Anti-inflammatory and analgesic potential of Caesalpinia ferrea

Caesalpinia ferrea Mart. belongs to the family Fabaceae. Known as pau-ferro and jucá, it is used in folk medicine to treat diabetes, as antipyretic and antirheumatic. This study aimed to evaluate the anti-inflammatory and antinociceptive activities of the ethanol extract of the fruits of C. ferrea (EECf). In the evaluation of anti-inflammatory activity, EECf (50 mg/kg) produced significantly inhibition of ear edema by 66.6 percent compared to control. Indomethacin (10 mg/kg) showed inhibition of 83.9 percent compared to control. EECf (50 mg/kg) inhibited of vascular permeability induced by acetic acid and was also able to reduce of cell migration to the peritoneal cavity induced by thioglycolate. In the writhing test induced by acid acetic, EECf (12.5, 25 and 50 mg/kg) significantly reduced the number of contortions by 24.9, 46.9 and 74.2 percent, respectively. In the formalin test, EECf presented effects only in the second phase. The results provided experimental evidence for the effectiveness of the traditional use of C. ferrea in treating various diseases associated with inflammation and pain.