The Antinociceptive Effects of Central and Peripheral Administration of Peganum harmala L. Extracts in Animal Models

The medicinal plant Peganum harmala has been used in traditional Moroccan medicine to accelerate the healing process of various diseases and to relieve the pain. The antinociceptive effect of the Aqueous (AE), Dichloromethane (DE) and Butanolic (BE) extracts of the Peganum harmala L. was tested in mice and rats by chemical and thermal models. Plant seed extracts were given intraperitoneally 30 min before the 0.6% acetic acid injection. Dichloromethane (DE) at doses of 25 mg/kg (68.4%; p<0.001), 50 mg/kg (79.75%; p<0.001), AE in doses 25 mg/kg (2.65%; p>0.05), 50 mg/kg (24.39%; p<0.05) and BE in doses 25 mg/kg (36.82%; p<0.001), 50 mg/kg (74.26%; p<0.001) induced decrease in torsional reaction relative to control group. The DE, BE and AE (25, 50 mg/kg, intraperitoneally injection (i.p.,); 60 µg/kg, intracerebroventricular injection (i.c.v.,)) extracts of P. harmala generated a significant latency increase in the tail-flick response to thermal stimulation and generated a significant increase in the reaction time in the hot plate test. Whereas in formalin test, DE, BE and AE revealed a significant impact on both phases when given by intraperitoneal route. The antinociceptive effect of extracts was lower than morphine (10 mg/kg, i.p.,) in the hot-plate test and in both the phases of formalin test. Data suggest that extracts of P. harmala have inhibitory activity on the mechanisms of peripheral and central pain. Analgesic activity of this plant could potentially be associated with the presence of alkaloids, flavonoids, tannins, saponins and steroids in all P. harmala (Linn) seed extracts. It seems that the reason of popular use to relieve some pains.