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Background and Objective: The degeneration of motor neuron in anterior horn of spinal cord can be caused by compression. Hyssopus officinalis of Laminacea family demonstrate antioxidant and anti-inflammation effects. This study was done to evaluate the effect of alcoholic extract of Hyssopus officinalis leaves, on motor neuron in spinal cord after sciatic nerve compression in male rats.

Methods: In this experimental research, 60 male wistar rats were randomly allocated into six groups including; control, compression, and compression + treatment (25, 50, 75, 100 mg/kg/bw). In order to induce compression, sciatic nerve of right leg was exposed to compression for 60 second using locker pincers. Extract injected intraperitoneally in the first and second week after compression. 28 days after compression under profusion method, the lumber spinal cord was sampled. The density of motor neurons (9-20 micron) was measured using dissector and stereological method.

Results: Density of neurons in compression group (611±34) significantly reduced compared to the control group (1658±30) (P<0.05). Moreover, neuronal density was significantly increased in
25 (1179±22), 50 (1260±20), 75 (1350±15) and 100 (1120±10) mg/kg/bw doses in treatment groups in compared to the compression group (P<0.05).

Conclusion: Alcoholic extract of Hyssopus officinalis leaves exhibite neuroprotective effect on neurons in anterior horn of the spinal cord after injury. This effect probably is related to the antioxidant and anti inflammation properties in alcoholic extract of Hyssopus officinalis, dose dependly.

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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.