Pharmacological effects of the aqueous extract of Neorautanenia mitis in rodents.

The pharmacological effects of the aqueous extract of Neorautanenia mitis (family Papilonaceae) were studied in rodents. Investigations were carried out on acetic acid-induced writhing (pain) in mice and hind paw oedema in rats. The effects of the extract were also studied on the isolated non-pregnant rat uterus and rabbit jejunum. Results showed the extract to possess significant (P<0.05) dose-dependent anti-nociceptive activity between 12.5 and 50.0 mg/kg p.o. in mice and slight anti-inflammatory activity at 25 and 50 mg/kg p.o. in rats. The extract also produced a concentration-dependent inhibition of the normal rhythmic contraction of the isolated non-pregnant rat uterus. It was found to inhibit oxytocin-induced as well as acetylcholine-induced contractions in the rat uterus. The extract also exhibited concentration-dependent inhibition of spontaneous contractions of the rabbit jejunum. Preliminary phytochemical analysis of the extract revealed the presence of saponin glycosides, flavonoids, tannins and alkaloids. The extract had an intraperitoneal (i.p.) LD(50) of 282.84+/-3.2 mg/kg in mice. These data corroborate the traditional use of this plant in the treatment of dysmenorrhea.