Neurophysiological study on possible protective and therapeutic effects of Sidr (Zizyphus spina-christi L.) leaf extract in male albino rats treated with pentylenetetrazol

In this study, anti-convulsant effect of Sidr leaf extract was examined by using pentylenetetrazol (PTZ) model on male albino rat by evaluating the changes in norepinephrine (NE), dopamine (DA) and serotonin (5-HT) contents in different brain regions (cerebellum, brainstem, striatum, cerebral cortex, hypothalamus and hippocampus). The administration of subconvulsive dose of PTZ (40 mg/kg i.p.) every other day for 9 days caused a significant decrease in monoamine content in different brain areas, this is may be due to the increase in nitric oxide levels, although antagonized the GABAA receptors which led to neurotransmitter release so the content is decreased. Administration of PTZ after treatment with Sidr (50 mg/kg i.p.) leaf extract for 3 weeks as a protective group and administration of Sidr leaf extract for 3 weeks after treatment of PTZ as a therapeutic group caused significant increase in NE, DA, and 5-HT contents in all tested brain regions at most of the time intervals studied. This may be due to the presence of peptide and cyclopeptide alkaloids in the extract which inhibit neurotransmitter activity which led to the inhibition of neurotransmitter release. From these results, we can say that the Sidr leaf extract has neuroprotective and therapeutic roles against pentylenetetrazol convulsant effect.