大鼠脑缺血早期阶段不同脑区NO和cGMP的变化

Changes of NO and cGMP in Different Brain Regions at Early Stage during Cerebral Ischemia in Rats

目的研究大鼠脑缺血后大脑皮质、海马、纹状体和小脑一氧化氮（ＮＯ）和ｃＧＭＰ的变化。方法采用荧光法和放射免疫法分别测定ＳＤ雄性大鼠（ｎ＝１０）脑缺血不同时点４个脑区ＮＯ代谢产物ＮＯ２和ｃＧＭＰ的含量。结果各脑区ＮＯ２的含量在脑缺血５ｍｉｎ开始升高，持续到缺血１５ｍｉｎ；缺血３０～６０ｍｉｎ开始下降；ｃＧＭＰ的含量在大脑皮质于缺血５～１５ｍｉｎ明显升高，在海马、纹状体和小脑于缺血１０～３０ｍｉｎ升高明显，脑缺血６０ｍｉｎ均下降。结论脑缺血早期出现ＮＯ的过量生成，提示用ＮＯ生成抑制剂以阻断脑缺血早期过量ＮＯ损伤作用。

Objective\ To study the changes of nitric oxide(NO) and cyclic guanosine monophosphate(cGMP) in cerebral cortex,hippocampus,striatum and cerebellum during early stage of cerebral ischemia in rats.\ Methods\ Nitrite(NO 2), the metabolite of NO,and cGMP in brain regions were measured with fluorometeric method and radioimmunoassay.\ Results\ NO 2 concentration in four regions significantly increased at 5～15 min,peaked at 15 min,decreased at 30～60 min after ischemia.cGMP concentration significantly increased at 5～15 min intervals in cortex,10～30 min in hippocampus、striatum and cerebellum,peaked at 10 min and decreased at 60min after ischemia.\ Conclusion\ These results indicated that brain NO and cGMP concentrations increase markly at early stage of cerebral ischemia,which involve in the cerebral brain damage.\ Using NO inhibitors to decrease the excessive production of NO at early stage may become a new treatment for cerebral ischemia.