Solà C, García-Ladona F J, Sarasa M, Mengod G, Probst A, Palacios G, Palacios J M
Department of Pharmacology and Toxicology, CID, CSIC, Barcelona, Spain.
Eur J Neurosci. 1993 Jul 1;5(7):795-808. doi: 10.1111/j.1460-9568.1993.tb00931.x.
The response of the beta APP gene to neuronal injury was studied in the facial and hypoglossal nerve nuclei of the rat after corresponding nerve axotomy. Increased levels of beta APP 695, 714, 751 and 770 mRNAs were observed after either facial or hypoglossal nerve axotomy in the parent ipsilateral motor neurons. The increase was gradual, with maximal values 7 days after axotomy. beta APP mRNA expression returned to normal values 60 days after the lesion. Increased beta APP immunostaining was also detected in ipsilateral chromatolytic motor neurons. No change in beta APP immunoreactivity was observed in oligodendrocytes, another cell type expressing beta APP under normal conditions. A rapid increase in the expression of the GFAP gene was observed in reactive astrocytes surrounding chromatolytic neurons in the ipsilateral facial or hypoglossal nuclei. Thus, in contrast with other models of neuronal injury, where only the Kunitz protease inhibitor-containing beta APP mRNA isoforms are increased, all beta APP mRNAs are increased in the axotomy model. Furthermore, although beta APP expression has been shown to be increased in reactive astrocytes following neuronal injury, in the present study the increase was essentially found in the motor neurons reacting to axotomy.
在大鼠相应神经轴突切断后，对面神经和舌下神经核中β-淀粉样前体蛋白（beta APP）基因对神经元损伤的反应进行了研究。在面神经或舌下神经轴突切断后，在同侧母运动神经元中观察到β-APP 695、714、751和770 mRNA水平升高。这种升高是渐进性的，在轴突切断后7天达到最大值。损伤后60天，β-APP mRNA表达恢复到正常水平。在同侧染色质溶解的运动神经元中也检测到β-APP免疫染色增加。在少突胶质细胞中未观察到β-APP免疫反应性的变化，少突胶质细胞是在正常条件下表达β-APP的另一种细胞类型。在同侧面神经或舌下神经核中，在围绕染色质溶解神经元的反应性星形胶质细胞中观察到胶质纤维酸性蛋白（GFAP）基因表达迅速增加。因此，与其他神经元损伤模型不同，在其他模型中只有含库尼茨蛋白酶抑制剂的β-APP mRNA亚型增加，而在轴突切断模型中所有β-APP mRNA均增加。此外，尽管已表明在神经元损伤后反应性星形胶质细胞中β-APP表达增加，但在本研究中，增加主要发生在对轴突切断有反应的运动神经元中。
