Expression of Heme-oxygenase 1 in the neonatal rat brain with hypoxic-ischemic encephalopathy.

血红素加氧酶1 （HO-1）是血红素降解的应激蛋白和限速酶，产生一氧化碳和胆色素。为了研究HO-1在新生儿缺氧-缺氧症（HI）中的作用，我们对1周龄的幼鼠进行左颈动脉结扎，并暴露于8% O2/92% N2中2小时。hii免疫组化染色显示，hii加载后6小时，HO-1阳性细胞在海马CA3区富集。Western blot分析显示，HI后12小时至24小时，海马和纹状体等同侧区域HO-1染色增加。ho -1水平在12小时达到峰值，并局限于局部。HI对新生大鼠脑HO-1 mRNA表达的影响。我们通过Northern blot分析研究了HI后新生大鼠脑HO-1的表达，发现HI后6小时缺血区HO-1表达水平升高。虽然HO-1产生的胆红素可能在许多组织中起到抗氧化剂的作用，但它也可能对新生儿的大脑有毒。

Heme-oxygenase 1 (HO-1) is a stress protein and a rate-limiting enzyme in heme degradation, generating carbon monoxide and bile pigment. To study the role of HO-1 in neonatal hypoxia-iachemia (HI), 1 week old wats were subjected to left carotid ligation and exposure to 8% O2/92% N2 for 2 hours.1.Expression of HO-1 in the neonatal rat brain after HIImmuno-histochemical staining revealed that HO-1 positive cells were rich in the CA3 region of hippocampus at 6 hours after HI loading. Western blot analysis showed increased HO-1 staining in the ipsilateral region including hipocampus and striatum at 12 hours upto 24hours after HI.The HO-1levels peaked at 12 hours, and were localized perifocally.2. Effect of HI on the expression of HO-1 mRNA in the neonatal rat brain.We studied HO-1 expression in the neonatal rat brain after HI by using Northern blot analysis, and found increased levels in the ischemic region at 6 hours after HI.Though the bilirubin produced by HO-1 may act as an antioxidant in many tissues, it may also be toxic to the neonatal brain.