Analgesic and anti-inflammatory activities of Polygonum stagninum

Figures & data

Table 1.  Effect of Polygonum stagninum extracts in mice observed in the acetic-acid-induced writhing test.

Group	Treatment	Dose* (mg/kg)	Mean writhings**	% Writhings	% Writhing inhibition
A	Control: DMSO (0.5 mL) in 2 mL of normal saline	—	37.8 ± 0.94	100 ± 3.06	0
B	Aminopyrine	50	14.3 ± 0.74	37.8 ± 3.02	62.2
C	n-Hexane extract	200	21.2 ± 0.54	56.1 ± 3.00	43.9
D	EtOAc extract	200	21.0 ± 0.93	55.6 ± 3.04	44.4
E	MeOH extract	200	30.4 ± 1.07	80.4 ± 3.00	19.6
F	n-Hexane extract	400	19.3 ± 1.03	51.1 ± 3.04	48.9
G	EtOAc extract	400	18.8 ± 0.90	49.7 ± 3.02	50.3
H	MeOH extract	400	27.9 ± 1.05	73.8 ± 3.02	26.2

*Administered orally (p.o.) 40 min before 0.2 mL of 0.7% acetic acid administration.

**Counted for 10 min, starting 10 min after acetic acid administration.

p < 0.05 vs. control, Students t-test; values are mean ± SE (n = 5).

Table 2.  Effect of Polygonum stagninum extracts in rats observed in the carrageenan-induced edema test.

Group	Treatment	Dose (mg/kg, p.o.)	Edema volume (µL) (% inhibition)
			1 h	2 h	3 h	4 h
A	Control (1% aq. Tween 80)	10 mL/kg	36.4 ± 2.15	64.6 ± 2.69	71.4 ± 0.83	63.0 ± 1.26
B	Phenylbutazone	100 (i.p.)	27.2 ± 0.79	42.4 ± 1.86	45.2 ± 1.94	38.6 ± 0.76
			(24.4)	(34.7)	(36.7)	(38.3)
C	n-Hexane extract	200	30.8 ± 2.94	25.8 ± 2.67	41.4 ± 1.51	49.8 ± 2.08
			(15.4)	(60.1)	(42.0)	(21.0)
D	EtOAc extract	200	27.4 ± 1.96	45.6 ± 2.55	51.6 ± 1.28	52.6 ± 3.08
			(24.7)	(29.4)	(27.7)	(16.5)
E	MeOH extract	200	27.6 ± 2.83	45.8 ± 3.12	55.2 ± 2.04	40.4 ± 1.31
			(24.2)	(24.5)	(22.7)	(35.9)
F	n-Hexane extract	400	29.4 ± 1.28	23.2 ± 1.11	40.6 ± 1.34	50.4 ± 1.84
			(19.2)	(64.1)	(43.1)	(20.0)
G	EtOAc extract	400	26.8 ± 1.39	45.2 ± 1.58	52.4 ± 2.34	55.2 ± 2.25
			(26.4)	(30.0)	(26.6)	(12.4)
H	MeOH extract	400	28.4 ± 0.92	46.2 ± 1.39	57.2 ± 2.36	39.84 ± 1.63
			(22.0)	(28.5)	(20.7)	(36.8)

The initial hind paw volume of the rat was determined volumetrically. Each point represents the mean ± SEM of five rats.

p < 0.05, compared with control group (Students t-test).

Inhibition (%) = 100(1 – (a/b)) where a = mean paw volume of treated animals after egg albumin injection; b = mean paw volume of control animals after egg albumin injection.