Carrageenan – induced paw oedema
The anti-inflammatory property of PIL was evaluated using carrageenan-induced oedema
on rat paw method, as described previously by Winter et al (16). The animals were
pretreated orally with PIL (10, 30, 100 and 300 mg/kg). Negative control animals
received a similar volume of 5% aqueous ethanol solution (oral) and positive control
animals received indomethacin (IND; 10 mg/kg) intraperitoneally. After 30 minutes, 0.1
ml of 1% w/v suspension of carrageenan was injected subcutaneously onto the plantar
surface of right hind paw to all the groups. Equal volume of saline was injected onto the
plantar surface of the left hind paw. The volumes of both hind paws of each rat were
measured using a Plethysmometer (Model 7140,Ugo Basile) at every half-hourly interval
until the period of four hours after the injection of the carrageenan. For a consistent
measurement, a line was marked just above the ankle joint of both rat’s hind limbs. Hind
paw swelling was measured when the paw was immersed at the line marked and was
calculated as oedema percentage (17) according to the formula