Background
Methods
Plant material and extraction
Animals
Drugs and treatments
Acute toxicity test
Antinociceptive analysis
Hot plate test
Tail immersion test
Acetic acid-induced writhing test
Formalin-induced nociception
Glutamate-induced nociception
Analysis of the possible mechanism of action of MECN
Involvement of opioid system
Involvement of ATP-sensitive K+ channel pathway
Statistical analysis
Results and discussion
Acute toxicity test
Hot plate and tail immersion tests
Treatment | Dose(mg/kg) | Response time (s) (%MPE) | ||||
---|---|---|---|---|---|---|
Pretreatment | 30 min | 60 min | 90 min | 120 min | ||
Control | 0.1 ml/mouse | 5.87 ± 0.20 | 6.30 ± 0.13 | 6.72 ± 0.09 | 8.62 ± 0.32 | 9.34 ± 0.25 |
Morphine | 5 | 6.67 ± 0.30 | 12.70 ± 0.51* (45.23) | 14.75 ± 1.03* (60.64) | 15.70 ± 0.86* (67.77) | 15.84 ± 0.94 (68.82) |
MECN | 50 | 5.72 ± 0.74 | 7.84 ± 0.63 (14.90) | 8.31 ± 0.43 (18.17) | 10.19 ± 0.60 (31.35) | 10.37 ± 0.51 (32.58) |
MECN | 100 | 6.71 ± 0.48 | 8.98 ± 0.56** (17.04) | 9.66 ± 0.12** (22.16) | 13.16 ± 0.89** (48.52) | 13.06 ± 1.66 (47.73) |
MECN | 200 | 5.83 ± 0.66 | 9.54 ± 0.21* (26.22) | 11.74 ± 0.72* (41.70) | 13.86 ± 1.12* (56.69) | 13.71 ± 1.78 (55.60) |
NLX | 2 | 7.22 ± 0.34 | 7.05 ± 0.18 | 6.85 ± 0.13 | 6.71 ± 0.29 | 5.30 ± 0.36 |
NLX + Control | 2 + 0.1 ml/mouse | 5.93 ± 0.27 | 6.15 ± 0.10 | 6.54 ± 0.19 | 8.01 ± 0.37 | 8.38 ± 0.69 |
NLX + Morphine | 2 + 5 | 6.41 ± 0.37 | 7.25 ± 0.40a (6.24) | 7.65 ± 0.16a (9.15) | 8.86 ± 0.26a (18.02) | 8.96 ± 0.19a (18.82) |
NLX + MECN | 2 + 50 | 5.98 ± 0.61 | 6.31 ± 0.38 (2.37) | 7.41 ± 0.22 (10.17) | 9.13 ± 0.79 (22.44) | 9.71 ± 0.46 (26.59) |
NLX + MECN | 2 + 100 | 5.95 ± 0.81 | 6.49 ± 0.76b (3.80) | 7.93 ± 0.46 (14.05) | 9.53 ± 0.61 (25.49) | 10.08 ± 1.00 (29.36) |
NLX + MECN | 2 + 200 | 6.18 ± 0.96 | 7.04 ± 0.41c (6.25) | 8.75 ± 1.02c (18.64) | 9.95 ± 1.33c (27.30) | 10.14 ± 0.59 (28.69) |
Treatment | Dose(mg/kg) | Response times (s) (%MPE) | ||||
---|---|---|---|---|---|---|
Pretreatment | 30 min | 60 min | 90 min | 120 min | ||
Control | 0.1 ml/mouse | 1.78 ± 0.17 | 2.01 ± 0.19 | 2.44 ± 0.09 | 2.77 ± 0.30 | 2.93 ± 0.29 |
Morphine | 5 | 1.62 ± 0.10 | 3.11 ± 0.37* (8.13) | 3.95 ± 0.27* (12.66) | 4.35 ± 0.28* (14.87) | 4.17 ± 0.24 (13.88) |
MECN | 50 | 1.75 ± 0.11 | 2.13 ± 0.11 (2.13) | 2.32 ± 0.04 (3.16) | 2.79 ± 0.19 (5.70) | 2.96 ± 0.06 (6.67) |
MECN | 100 | 1.91 ± 0.13 | 2.63 ± 0.33 (3.98) | 3.06 ± 0.53 (6.36) | 4.15 ± 0.59* (12.37) | 4.28 ± 0.59* (13.08) |
MECN | 200 | 1.81 ± 0.14 | 3.03 ± 0.26* (6.67) | 3.75 ± 0.17* (10.66) | 4.26 ± 0.34* (13.46) | 4.58 ± 0.26* (15.20) |
NLX | 2 | 1.91 ± 0.11 | 2.23 ± 0.17 | 2.29 ± 0.19 | 2.30 ± 0.17 | 2.22 ± 0.32 |
NLX + Control | 2 + 0.1 ml/mouse | 1.68 ± 0.15 | 1.97 ± 0.08 | 2.11 ± 0.10 | 2.14 ± 0.13 | 2.27 ± 0.16 |
NLX + Morphine | 2 + 5 | 1.94 ± 0.18 | 2.08 ± 0.08 (0.80) | 2.52 ± 0.05a (3.26) | 2.95 ± 0.14a (5.64) | 3.11 ± 0.11 (6.50) |
NLX + MECN | 2 + 50 | 1.91 ± 0.16 | 2.08 ± 0.07 (0.94) | 2.11 ± 0.08 (1.12) | 2.13 ± 0.32 (1.22) | 2.20 ± 0.38 (1.61) |
NLX + MECN | 2 + 100 | 1.78 ± 0.11 | 2.10 ± 0.13 (1.75) | 2.21 ± 0.11 (2.38) | 2.32 ± 0.04b (2.99) | 2.71 ± 0.15 (5.12) |
NLX + MECN | 2 + 200 | 1.95 ± 0.11 | 2.20 ± 1.10 (1.38) | 2.41 ± 0.14c (2.56) | 2.55 ± 0.07c (3.33) | 2.80 ± 0.06c (4.69) |
Acetic acid writhing test
Treatment | Dose(mg/kg) | Responses | |
---|---|---|---|
Number of writhing (Mean ± SEM) | % Inhibition | ||
Control | 0.1 ml/mouse | 65.90 ± 2.05 | - |
Diclofenac sodium | 10 | 20.00 ± 0.79* | 69.65 |
MECN | 50 | 59.10 ± 3.74 | 10.32 |
MECN | 100 | 32.20 ± 1.41* | 51.14 |
MECN | 200 | 22.70 ± 0.91* | 65.55 |
Formalin induced nociception
Treatment | Dose (mg/kg) | Licking number | % Inhibition | ||
---|---|---|---|---|---|
(Mean ± SEM) | |||||
Early phase | Late phase | Early phase | Late phase | ||
Control | 0.1 ml/mouse | 143.20 ± 2.11 | 149.60 ± 3.61 | - | - |
Diclofenac sodium | 10 mg/kg | 28.40 ± 1.36* | 7.40 ± 0.51* | 80.17 | 95.05 |
MECN | 50 mg/kg | 126.60 ± 7.52 | 87.40 ± 4.50* | 11.59 | 41.58 |
MECN | 100 mg/kg | 111.40 ± 4.58* | 50.20 ± 2.44* | 22.21 | 66.44 |
MECN | 200 mg/kg | 71.20 ± 0.97* | 39.60 ± 2.89* | 50.28 | 73.53 |
Glutamate induced nociception
Treatment | Dose(mg/kg) | Responses | |
---|---|---|---|
Number of licking (Mean ± SEM) | % Inhibition | ||
Control | 0.1 ml/mouse | 157.20 ± 4.87 | 0 |
Diclofenac sodium | 10 | 49.60 ± 1.08* | 68.45 |
MECN | 50 | 59.60 ± 2.25* | 62.09 |
MECN | 100 | 49.00 ± 2.39* | 68.83 |
MECN | 200 | 39.80 ± 3.53* | 74.68 |
Involvement of opioid system and ATP-sensitive K+ channel pathway
Treatment | Dose (mg/kg) | Responses | |
---|---|---|---|
Number of writhing (Mean ± SEM) | % Inhibition | ||
Control | 0.1 ml/mouse | 73.90 ± 1.61 | - |
Diclofenac sodium | 10 | 19.90 ± 0.53* | 73.07 |
MECN | 50 | 54.70 ± 1.83* | 25.98 |
MECN | 100 | 29.90 ± 0.66* | 59.54 |
MECN | 200 | 18.30 ± 1.25* | 75.24 |
Glib | 10 | 75.1 ± 2.01 | −1.62 |
Glib + Diclofenac-sodium | 10 + 10 | 36.20 ± 1.77a
| 51.05 |
Glib + MECN | 10 + 50 | 50.00 ± 1.53 | 32.34 |
Glib + MECN | 10 + 100 | 28.00 ± 2.13 | 62.11 |
Glib + MECN | 10 + 200 | 20.00 ± 1.34 | 72.94 |