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Background & objectives: Syzygium aromaticum (Clove) is a medicinal plant usually used in traditional medicine to reduce toothache. The aim of the present study was to evaluate the analgesic effect of topical Clove oil on acute and chronic pain in male mice using formalin test.
Methods: In this study, 24 mice were divided into 4 groups: control, morphine (as positive control), Clove oil, and Clove oil plus morphine groups. Before the formalin test, the animals were treated topically with clove oil for 6 hours.  A single dose of morphine (10 mg/kg) was prescribed subcutaneously. Pain scores were obtained using the formalin test through an injection of 20 microliter of formalin 2.5% into the palm of the animal's right hand.
Results: Topical administration of Clove oil significantly decreased acute pain (the initial phase of the formalin test) and chronic pain (the second phase of the formalin test). Furthermore, topical Clove oil increased the analgesic effect of morphine in acute pain phase.
Conclusions: This study showed that the analgesic effect of topical Clove oil was comparable to morphine.

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CT
 
Background & objectives: So far, various reports have been presented on the relationship between sex hormones and gender-related differences in pain and analgesia in humans and laboratory animals. The purpose of this study was to investigate the effect of testosterone hormone and spironolactone anti-androgen drug on morphine-induced analgesia in male mice using formalin test.
Methods: In this study, 80 male mice were divided into 10 groups (N=8); normal saline (control), sesame seed oil (as testosterone solvent), testosterone (5 and 10 mg/kg body weight), spironolactone, morphine, sesame seed oil + morphine, testosterone (5 and 10 mg/ kg body weight) + morphine and spironolactone + morphine. Formalin test was performed in all the mice, and data were analyzed by one-way ANOVA.
Results: The results showed that sesame seed oil + morphine (p<0.001), morphine (p<0.001), testosterone (5 mg/kg) + morphine (p<0.01) and testosterone (10 mg/kg) + morphine (p<0.001) significantly reduced acute  pain, and testosterone (5 mg/kg) (p<0.05), testosterone (10 mg/kg) (p<0.01), sesame seed oil + morphine (p<0.001), morphine (p<0.001), testosterone (5 mg/kg) + morphine (p<0.001) and testosterone (10 mg/kg) + morphine (p<0.001) significantly reduced chronic pain compared with control group. Spironolactone had no effect on pain relief in the presence and absence of morphine compared to control group.
Conclusions: It can be concluded that testosterone has analgesic effects on the chronic phase of the pain. On the other hand, spironolactone may have hyperalgesic effects due to its anti-androgenic properties.

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Background & objectives: In recent years, regarding the side effects of chemical drugs, the use of medicinal plants has increased due to their low side effects, low costs and effective compounds. The aim of this study was to investigate the anti-inflammatory, anti-nociceptive, and anti-pyretic effects of hydroalcoholic extract of Rosa canina L. fruit in male mice.
Methods: In this experimental study, 120 male BALB/c mice weighing 23-30 g were used. In each test, the mice were divided into 5 groups (in each group, n=6), including control group, positive control and three experimental groups treated intraperitoneally with hydroalcoholic extract of Rosa canina L. fruit at doses of 100, 200 and 400 mg/kg respectively. The anti-inflammatory and antipyretic activities were measured using xylene-induced ear edema and brewer’s yeast-induced pyrexia tests, respectively. In addition, the antinociceptive activity was measured using the abdominal constrictions induced by acetic acid and formalin tests. The data were analyzed by SPSS statistical software and One Way ANOVA test. The level of significance was set at   p<0.05.
Results: 200 (p<0.05) and 400 mg/kg (p<0.001) doses of extract reduced significantly inflammation. Doses of 100 (p<0.05), 200 (p<0.01) and 400 (p<0.001 significantly reduced pain in the abdominal constriction test and dose of 400 mg/kg (p<0.05) decreased the chronic pain in formalin test. Extract treatment did not reduce fever in any of the existing doses.
Conclusions: The findings of this study suggest that Rosa canina L. fruit has anti-inflammatory and visceral analgesic activity, which may be due to its antioxidant potential.
 

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Background & objectives: The pathophysiology of depression is very complex. Rosa canina L fruit contains various antioxidant compounds. The aim of this study was to investigate the anti-depressant and anti-anxiety effects of the aqueous- alcoholic extract of the Rosa canina L fruit in the behavioral tests including forced swimming, tail suspension, maze, and sucrose preference tests, as well as biochemical tests such as antioxidant capacity and malondialdehyde levels. Rosa canina L with high amounts of vitamin C, has anti-depressant and anxiety effects.
Methods: In this experimental study, 60 Syrian male mice were divided into 5 groups of 12, including the control group, the bisphenol A group, and three groups treated with oral bisphenol A at a dose of 125 mg/kg per day and the aqueous- alcoholic extract of the Rosa canina L fruit at doses of 100, 200, 400 mg/kg/day was administered from day 50 to 120 after birth. The data were analyzed using SPSS statistical software and the One Way ANOVA test. The level of significance was set at p<0.05.
Results: The findings showed that bisphenol A significantly increased the duration of immobility in the forced swimming and tail suspension test. The extract at the level of 400 mg/kg decreased the duration of immobility in both tests. Bisphenol A significantly reduced the antioxidant capacity of serum and brain. The extract at the level of 400 mg/kg significantly increased the antioxidant capacity of both the brain and serum.
Conclusion: The findings of this research showed that the fruit of the Rosa canina L has antioxidant effects, and with a significant decrease in antioxidant capacity and immobility in Syrian mice treated with the extract, therefore it has anti-depressant and anxiety effects.