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AIM:To investigate the time course of nuclear factor-κB (NF-κB) and the effects of 3-aminobenzamide (3-AB) on the expressions of NF-κB,interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) in hippocampus after seizures. METHODS:Epilepsy were induced by kainic acid through cerebral ventricular injection. Western blotting was used to detect NF-κB p65 expression in nucleus at various experiment groups. Moreover,mRNA and protein expressions of IL-1β and COX-2 in different experiment groups were determined by RT-PCR and Western blotting analysis. RESULTS:NF-κB p65 immunoreactivity began to increase in the nuclear fraction at 2 h (P<0.05),kept rising at 12 h (P<0.05) and returned to control level at 24 h after epilepsy seizures. Furthermore,3-AB sharply decreased the accumulation of NF-κB p65 in nucleus (P<0.05). In addition,3-AB significantly decreased the mRNA and protein expressions of IL-1β and COX-2 which obviously increased in hippocampus at 6 h after epilepsy seizures (P<0.05). CONCLUSION:Seizures triggers NF-κB nucleus translocation and promotes the expressions of IL-1β and COX-2 in hippocampus. In addition,poly (adenosine diphosphate-ribose) polymerase inhibition by 3-AB suppresses NF-κB associated inflammatory pathway in epileptic rat hippocampus.
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Objective To establish a primary culture method of hippocampal neurons of new-born rats,and to observe the morphological characteristics at different developmental and differential stages.Methods The hippocampus was digested and the cells were seeded in a flask.The neurons were then transferred and re-seeded on cover glasses coated with poly-L-lysine.The neurons were identified by polyclonal antibody against neuron specific enolase(NSE).The morphology was observed under phase-contrast microscope.Results A large number of hippocampal neurons began to adhere to the cover glasses after 12～24 hours.They showed different shapes-shuttle,triangle,pyramidal,or nonregular after clinging to the plate.Their processes connected into nets and different in length and thickness.They were well developed on the 7th～10th day and survived as long as 28 days after seeding.Immunocytochemistry of NSE proved high purity.Conclusion The culture method of new-born rat hippocampal neurons in vitro is successful and can be used as an in vitro model of research.
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Objective To observe the morphology of neuronal necrosis by kainic acid(KA) induced status epilepsy (SE) in rats, and to study the brain protective effect of Mg 2+.Methods 75 adult male Wistar rats were randomly divided into KA group, Mg 2+ group and normal saline group. SE was induced with KA for 3 hours, and the rats in Mg 2+ group were intraperitoneal injected magnesium sulfate before being injected KA. 72 hours later the rats were killed. We had all rat brain sections and observe the morphology of neuronal necrosis with microscope and electron microscope.Results In KA group, seizure was induced 16.1?4.7 min after injection of KA, but seizure delayed to 25.4?6.2 min in Mg 2+ group. There was a significant difference between two groups (P
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Objective To study the role of gap junctions in epileptiform activity. Methods The epileptiform activity was induced by zero-Mg 2+ medium in cultured hippocampal neurons of newborn rats. Immunocytochemistry and real time RT-PCR were introduced to evaluate the expression of gap junction Cx32 and Cx43. Results The level of Cx32 mRNA increased quickly one hour after the neurons were treated with zero-Mg 2+ medium and was raised by 10 times 5 hours later, while Cx32 protein began to develop at the 2nd hour (21.80?1.74) and was raised by 5 times at the 8th hour (47.30?5.75). The expression of Cx43 mRNA went up obviously 5 hours later, and Cx43 protein developed visibly 8 hours later. Carbenoxolone depressed the expressions of Cx32 and Cx43. Conclusions The expression of Cx32 and Cx43 increases dramatically after epileptic discharges and carbenoxolone inhibits both the discharges and the expression of gap junctions, which indicates that gap junction could contribute to epileptogenesis.
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AIM:To investigate the time course of nuclear factor-?B (NF-?B) and the effects of 3-aminobenzamide (3-AB) on the expressions of NF-?B,interleukin-1? (IL-1?) and cyclooxygenase-2 (COX-2) in hippocampus after seizures. METHODS:Epilepsy were induced by kainic acid through cerebral ventricular injection. Western blotting was used to detect NF-?B p65 expression in nucleus at various experiment groups. Moreover,mRNA and protein expressions of IL-1? and COX-2 in different experiment groups were determined by RT-PCR and Western blotting analysis. RESULTS:NF-?B p65 immunoreactivity began to increase in the nuclear fraction at 2 h (P