神经生长因子对脊髓损伤后脊髓组织c-fos蛋白表达的影响

Effect of NGF on c fos Gene Expression in Spinal Neuron After SCI

为探讨神经生长因子（ＮＧＦ）对脊髓损伤后脊髓组织ｃ－ｆｏｓ基因表达的影响。Ｗｉｓｔａｒ大鼠随机分成三组：正常对照组、生理盐水组、ＮＧＦ组；用ＡｌｅｎＷＤ法以１０ｇ×２．５ｃｍ致伤力损伤Ｔ８脊髓。ＮＧＦ组经蛛网膜下腔导管分别于术后即刻、１０、３０分、１、２、３、４小时注入ＮＧＦ溶液２０μｌ（含ＮＧＦ６０μｇ），生理盐水组经导管于同时间内注入等量的生理盐水。用免疫组化法检测ｃ－ｆｏｓ蛋白在脊髓组织中的表达。结果示生理盐水组在术后１５分ｃ－ｆｏｓ蛋白表达开始增多，术后２小时表达达高峰；ＮＧＦ组能抑制脊髓损伤后ｃ－ｆｏｓ蛋白的表达。结论：ＮＧＦ通过抑制损伤后ｃ－ｆｏｓ基因表达，从而保护了神经元并抑制继发性损害的发生，这可能是ＮＧＦ保护脊髓损伤作用机理之一。

Forty five rats with 10 g×2.5 cm impact T 8 SCI animals were divided into 3 groups. The experimental animals received 60 μg NGF purified from bovine seminal plasma at once, 15 min, 1, 2, 4 hours after injury, and an equal volume of normal saline was given to the control group at the same time. The c fos protein levels were detected by immunohistochemical methods. The results showed no evident c fos expression in normal control group. The c fos expression increased markedly in damaged neurons. The peak value of c fos protein happened at 2 hours; and c fos levels in NGF group reduced evidently. The experiment showed NGF can inhibit c fos expression. It may be one of the mechanisms by which NGF protects spinal cord against injury.