The changes of hippocampal NO on pentylenetetrazol induced epileptic rats and its effect to hippocampal neuronal apoptosis

Abstract

Objective To study the changes of nitric oxide (NO) content in hippocampus of rat by Pentylenetetrazol ( PTZ)-induced seizures models and its effect of toxicity and apoptosis.Methods SD male rats were random divided into three groups,each group has 14 rats.Group A is the saline control group,group B is the pentylenetetrazol induced epileptic group and group C is aminoguanidine ( NOS inhibitor) pretreatment plus pentylenetetrazol induced epileptic group.NO content in rat hippocampus was detected by ultraviolet spectrophotometry,glutamate ( Glu ) immunoreactivity in rat hippocampus was detected by immunohistochemistry (SABC) and caspase-3 mRNA levels in rat hippocampus were detected by reverse transcription-polymerase chain reaction (RT-PCR) respectively at 2,48 h after modeling.Results Group A had no seizure,group B had epilepsia gravior over Ⅴ grade,rats in group C had seizure over Ⅱ Ⅲ grade.The NO content on group B (75.67 ± 2.04) μ mol/L was significantly higher than group A (11.90±0.64) μmol/L and group C (36.19 ±4.48) μmol/L (P＜0.05) ; Glu immunoreactivity and caspase-3 mRNA leves of group A and group C were lower than group B ( P ＜ 0.05 ).Conclusion PTZinduced seizures may lead to excessive production of NO in hippocampus,which had excited toxicity to hippocampal neurons.The intervention of NOS synthetic inhibitor had neuroprotective effects. Key words: Epilepsy; Nitric oxide; Glutamate; Caspase-3 ; Apoptosis