Yang Zhi-xian, Qin Jiong, DU Jun-bao, Chang Xing-zhi, Han Ying
Department of Pediatrics, Peking University First Hospital, Beijing 100034, China.
Zhonghua Yi Xue Za Zhi. 2005 Mar 2;85(8):551-4.
Febrile seizures (FS) are the most common type of seizure disorders. Studies have found that there have respective changes of heme oxygenase (HO)/CO system and nitric oxide synthase (NOS)/NO system during FS. The present study was to explore the influence on expression of HO-1 mRNA and protein and content of CO after recurrent FS by NOS inhibitor N(omega)-nitro-L-arginine Methyl ester (L-NAME), in order to demonstrate a regulating role in HO/CO system by NO.
Forty-eight SD rats were randomly divided into 3 equal groups: FS group, undergoing intraperitoneal injection of normal saline (NS) and then bath in 45.2 degrees C hot water for 5 minutes every other day for 10 times, FS + L-NAME group, undergoing intraperitoneal injection of NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) and then FS for 10 times, and control group, undergoing intraperitoneal injection of NS and then bath in 37.0 degrees C water. Twenty-four hours after the last bath blood was collected from the abdominal cardinal vein to measure the concentrations of plasma nitric oxide and carbon monoxide with spectrophotometer. The brains were taken out to be made into frozen slices to undergo HO-1 in situ hybridization to measure the mRNA expression of HO-1. The hippocampus was taken out to undergo Western blotting to measure the expression of HO-1 protein.
The plasma CO concentration was higher by 94.5% in the FS group in comparison with that in the control group (P < 0.01). The plasma CO concentration of the FS + L-NAME group was higher by 63.18% than that of the control group (P < 0.05) and lower by 16.14% than in the FS group (P < 0.05). The HO-1 mRNA expression was significantly higher in the FS group than in the control group. The HO-1 mRNA expression of the in hippocampal neurons of the L-NAME was lower than that of the FS group, however, still higher than that of the control group. Western blotting showed that HO-1 protein was expressed in all 3 groups; the HO-1 protein expression of the FS group was higher by 208% than that of the control group; and the HO-1 protein expression of the FS + L-NAME group was higher by 115% than that of the control group (P < 0.01) and lower by 30.19% than that of the FS group (P < 0.01).
热性惊厥（FS）是最常见的惊厥性疾病类型。研究发现，FS发作时血红素加氧酶（HO）/一氧化碳（CO）系统和一氧化氮合酶（NOS）/一氧化氮（NO）系统各自发生了变化。本研究旨在探讨NOS抑制剂N（ω）-硝基-L-精氨酸甲酯（L-NAME）对反复FS后HO-1 mRNA和蛋白表达及CO含量的影响，以阐明NO对HO/CO系统的调节作用。
48只SD大鼠随机分为3组，每组16只：FS组，腹腔注射生理盐水（NS），然后每隔一天置于45.2℃热水中浸泡5分钟，共10次；FS + L-NAME组，腹腔注射NOS抑制剂N（ω）-硝基-L-精氨酸甲酯（L-NAME），然后进行FS 10次；对照组，腹腔注射NS，然后置于37.0℃水中浸泡。末次浸泡24小时后，从腹主动脉采血，用分光光度计测定血浆一氧化氮和一氧化碳浓度。取出脑组织制成冰冻切片，进行HO-1原位杂交，测定HO-1的mRNA表达。取出海马组织进行蛋白质印迹法检测HO-1蛋白表达。
FS组血浆CO浓度比对照组高94.5%（P < 0.01）。FS + L-NAME组血浆CO浓度比对照组高63.18%（P < 0.05），比FS组低16.14%（P < 0.05）。FS组HO-1 mRNA表达明显高于对照组。L-NAME处理的海马神经元中HO-1 mRNA表达低于FS组，但仍高于对照组。蛋白质印迹法显示，3组均有HO-1蛋白表达；FS组HO-1蛋白表达比对照组高208%；FS + L-NAME组HO-1蛋白表达比对照组高115%（P < 0.01），比FS组低30.19%（P < 0.01）。
