暴露丙烯酰胺对Wistar大鼠学习记忆及海马CA1区c-Fos表达的影响

Effects of acrylamide exposure on learning and memory,expressions of c-Fos expression in CA1 area of hippocampus in Wistar rats

目的:探讨丙烯酰胺(ACR)暴露对Wistar大鼠学习记忆能力、大脑海马CA1区c-Fos蛋白和c-fos mRNA表达的影响。方法:健康雄性Wistar大鼠40只,体重180~220g,随机分为对照组、腹腔注射ACR9mg/kg组、18mg/kg组和36mg/kg组,每组各8只,对照组以同样方式腹腔注射等量生理盐水。1周后用Morris水迷宫法检测大鼠学习记忆功能,HE染色观察海马CA1区神经细胞形态,用免疫组化法检测海马CA1区c-Fos蛋白表达,RT-PCR法检测c-fos基因表达。结果:ACR组大鼠表现为海马CA1区神经纤维稀疏、神经细胞减少,可见空泡样变性等。与对照组比较,ACR作用后大鼠学习记忆功能明显降低(P<0.05),且具有剂量依赖性(r=0.820~0.891,P均<0.05)。ACR中、高剂量组海马区c-Fos蛋白和c-fosmRNA表达水平明显低于对照组(P<0.01),同时随ACR剂量增加,c-Fos蛋白和c-fosmRNA表达水平降低,与ACR剂量明显相关(r=-0.824,0.857,P均<0.05)。结论:模型大鼠暴露于ACR可以损害学习记忆功能,同时有海马区c-Fos蛋白和c-fosmRNA表达水平下降,其机制可能是ACR造成大鼠海马区神经细胞功能减弱所致。

Objective: To investigate the effects of acrylamide ( ACR) exposure on learning and memory ability, expressions of c-Fos protein and c-fos mRNA in CA1 area of hippocampus in Wistar rats.Methods: Forty healthy male Wistar rats weighing 180 ~ 220 g were randomly divided into control group,intraperitoneal injection of ACR 9 mg /kg group,18 mg /kg group and 36 mg /kg group.Each group was 8 rats,while the control group received intraperitoneal injection of the same amount of normal saline in the same way.After 1 week,the learning and memory function of the rats was detected by Morris water maze.The morphology of neurons in hippocampal CA1 area was observed by HE staining.The expression of c-Fos protein in hippocampal CA1 area was detected by immunohistochemistry,and the expression of c-fos gene was detected by RT-PCR.Results: In ACR group,the nerve fibers in CA1 area of hippocampus were sparse, the nerve cells were decreased and vacuole-like degeneration was observed.Compared with the control group,the learning and memory function of the rats after exposure to ACR was significantly lower ( P<0.05) ,and had a dose effect correlation ( r = 0.820 - 0.891,P<0.05) .The expression levels of c-Fos protein and c-fos mRNA in hippocampus of ACR middle and high dose group were significantly lower than those of control group ( P<0.01) .At the same time,the expression of c-Fos protein and c-fos mRNA decreased with the increase of ACR dose,which was negatively correlated with ACR dose ( r = - 0.824,0.857,P<0.05) .Conclusion: The exposure to ACR can damage the learning and memory function in the rats,while the expression level of c-Fos protein and c-fos mRNA decreases in hippocampal CA1 area.The mechanism may be that ACR causes the weakening of neurons in the hippocampus of rats by ACR.