Zeinieh Michele P, Talhouk Rabih S, El-Sabban Marwan E, Mikati Mohamad A
Department of Biology, American University of Beirut, Beirut, Lebanon.
Brain Dev. 2010 Nov;32(10):810-7. doi: 10.1016/j.braindev.2009.11.003. Epub 2010 Jan 19.
Acute hypoxia at postnatal day (P) 10 is an accepted model of human neonatal hypoxia which results, among other consequences, in increased hippocampal excitability. Hypoxic-ischemic injury, which mimics stroke, has been shown to result in changes in connexins (Cxs), however, changes in Cxs have not been studied in the P10 hypoxia model. The aim of this study was to investigate changes in the hippocampal expression of three different connexins at consecutive developmental stages after acute hypoxia at P10 (10min and 30min after reoxygenation, P11, P14, P17, P29, and P45) as compared to sham manipulated pups. After acute hypoxia at P10, Cx30 protein levels were increased at 30min after reoxygenation, at P11 and at P14, and then returned to control levels. Cx36 protein levels transiently decreased at P11 after acute hypoxia then returned to control levels. Cx43 protein levels did not change at any of the time points. Although changes in mRNA expression were observed during development for Cx30 only, acute hypoxia did not result in changes in mRNA expression of all these Cxs when compared to age matched controls suggesting that acute hypoxia induced posttranslational changes in protein expression.
出生后第10天（P10）的急性缺氧是一种公认的人类新生儿缺氧模型，除其他后果外，该模型会导致海马兴奋性增加。缺氧缺血性损伤模拟中风，已被证明会导致连接蛋白（Cxs）发生变化，然而，在P10缺氧模型中尚未研究Cxs的变化。本研究的目的是调查与假手术处理的幼崽相比，在P10急性缺氧后连续发育阶段（复氧后10分钟和30分钟、P11、P14、P17、P29和P45）三种不同连接蛋白在海马中的表达变化。P10急性缺氧后，复氧后30分钟、P11和P14时Cx30蛋白水平升高，然后恢复到对照水平。急性缺氧后P11时Cx36蛋白水平短暂下降，然后恢复到对照水平。Cx43蛋白水平在任何时间点均未发生变化。虽然仅在Cx30的发育过程中观察到mRNA表达变化，但与年龄匹配的对照组相比，急性缺氧并未导致所有这些Cxs的mRNA表达发生变化，这表明急性缺氧诱导了蛋白质表达的翻译后变化。
