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Background & Objective: Black pepper is frequently used in Iranian traditional medicine as an analgesic (E.g, for toothache). This investigation was conducted to evaluate the response of mice to pain induced by hot-plate and Formalin test either with or without Piperine (One of the active substances of the pepper). Materials & Methods: This randomized experimental study was performed on mice. Hot-plate and Formalin tests were planned to pain measurement. The mice were divided into 2 groups in each arm of study (Hot-plate and Formalin test group). The data of control (Saline) and drug (Piperine) groups were separately compared in each arm of study with student t-test and ANOVA. The difference between each point of data was considered significant at P-value under 0.05. Results: There was not a significant difference in tolerance time of subjects between hot-plate and saline groups. Piperine (25, 50 and 75 mg/kg) along with Morphine (10 mg/kg) causes significant increase to saline group in tolerance time and also significant increase to Morphine group, but in Formalin test Piperine could have significant effect in decreasing the pain induced by of Formalin on mice. These effects are comparable with Morphine. In Formalin test, pain has 2 phases. The first phase is acute and the 2nd one is chronic that begins from 15-20 minutes. Acute pain has central effect and chronic pain has peripheral pathway and Piperine causes decreasing response to Formalin test at the first phase of pain. Naloxone can prevent these effects in all groups. In Formalin test and hot-plate, the effect of Piperine were dose dependent. Conclusion: Piperine can centrally act on the nociception pathway and its effect on Opioid system exhibits as an enhancement Opioid effect. The effects are dose dependent and will be inhibited by Opioid antagonist.

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Background & Objective: Hyperalgesia is considered as one of the marked signs of subchronic diabetes mellitus that could affect the life style of the patients. Considering the evidence on antidiabetic effect of Allium ampeloprasum (AA), this study was designed to investigate the analgesic effect of Allium ampeloprasum on formalin-induced nociceptive response in streptozotocin (STZ)-induced diabetic rats.

 

Materials & Methods: 45 male rats were randomly divided into control, AA-treated control, diabetic, sodium salicylate (SS)-treated diabetic, and AA-treated diabetic groups. For induction of diabetes, STZ was used at a 60mg/kg dose. The treatment groups received oral administration of AA-mixed pelleted food (6.25%) for one month. After one month, for all animals, blood glocuse concentration and formalin test measured. Data analyzed with using student paird t-test and ANOVA.

 

Results: The results showed that diabetic rats exhibited a higher score of pain at both phases of the formalin test (p<0.05) and AA treatment for one month did cause an improvement in this regard (p<0.05). Meanwhile, SS administration significantly reduced pain score only at chronic phase of the test (p<0.05).

 

Conclusion: This study indicated that one month administration of Allium ampeloprasum could attenuate nociceptive score in an experimental model of diabetes mellitus.

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Background and Objective: Finding the pain relieving substances is one of the important aims of biological researches. This study was done to evaluate the antinociceptive, anti-inflammatory effects of Hyssopus officinalis extract in mice.
Methods: In this experimental study, 100 male adult mice were allocated into 5 experimental groups including control group receiving only normal saline and groups that received extract of Hyssopus officinalis at doses of 25, 50 and 75 mg/kg/bw, and positive control group in formalin test received morphine in acute and chronic phase of experiment and positive control group in anti-inflammatory test received dexamethasone. Formalin-induced paw licking was used to determine the anti-nociceptive activity of Hyssopus officinalis extract. The anti-inflammatory activity was determined by Xylene test.
Results: In the acute phase of pain (the first 5 minutes), doses of 50 and 75 mg/kg/bw (7.75±2.3, 8.75±2.1) of the Hyssopus officinalis extract significantly reduced the number of feet raised (P<0.05). Also, in the chronic phase of pain (20 min second), 25, 50 and 75 mg/kg/bw of doses (17.25±2.3, 11.75±2.9, 2.7±10.75) and morphine significantly reduced the duration of foot lift (P<0.05). The extract of Hyssopus officinalis with three doses of 25, 50 and 75 mg/kg/bw (13.33±3.1, 20±3.1, 19.83±2.8) showed high anti-inflammatory activity against Xylene induced ear edema (P<0.05).
Conclusion: This study showed that Hyssopus officinalis extract can inhibit pain and inflammation in animal model.