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Background and Objective: Compression or sciatic axotomy induces neuronal death in spinal cord alpha motor neuron. This study was carried out to determine the effect of Nigella sativa seed alcoholic extract on spinal motor neuron density in anterior horn after sciatic nerve compression in rat. Materials and Methods: In this experimental study 24 wistar rats were divided into four groups A: control, B: compression, C: compression+treatment with 75 mg/kg alcoholic extract, D: compression+treatment with 50 mg/kg alcoholic extract. In control group muscle was exposed without any injury to sciatic nerve. In compression and treatment group, the right leg sciatic nerve compressed for 60 sec. After four weeks of post operation, L2-L4 and S1, S2 and S3 segments of spinal cord were sampled, processed, serially sectioned and stained with toluidine blue. The number of alpha motor neurons was counted using dissector method. Results: Neuronal density in compression group (650±32) significantly decreased in comparison with control group (1803±24). Neuronal density in C treated group (1581±47) and D treated group (1543±49) significantly increased compare to compression group (P<0.001). Conclusion: Alcoholic extract of Nigella sativa seed increased the density of alpha motor neurons in spinal cord after sciatic nerve compression in rats.

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Background and Objective: Bisphenol A (BPA) is an endocrine disruptor chemical and as an environmental pollutant is able to generate free radicals causing tissue damage. This study was done to investigate the effect of Nigella sativa oil against BPA induced toxicity on the tissue of male NMRI mice kidney by stereological method.

Methods: In this experimental study 24 adult male NMRI mice (32±3 g) were randomly allocated into control, BPA (200 mg/kg/day), BPA (200 mg/kg/day) plus Nigella sativa oil (5 ml/kg/day) and Nigella sativa oil (5 ml/kg/day) groups and treated for 5 weeks, orally. At the end, animals were sacrificed, their left kidneys were removed, fixed, sectioned, processed and stained with Heidenhain' azan staining method. Then, the kidney tissue sections were evaluated using stereological method and serum malondialdehyde (MDA) level was also measured.

Results: The total weight and volume of kidney, volume of cortex, volume of proximal and distal tubules and volume of their lumen, volume of interstitial tissue, volume of glomeruli, tuft, as well as serum MDA level significantly increased in BPA treated group compared to the controls (P<0.05). These parameters were significantly reduced in BPA plus Nigella sativa oil group compared to BPA ones (P<0.05).

Conclusion: This study revealed that Nigella sativa oil can reduce the oxidative stress toxicity induced by BPA in the mice renal tissue.