Lindefors N, Ernfors P, Falkenberg T, Persson H
Department of Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Exp Brain Res. 1992;88(1):78-90. doi: 10.1007/BF02259130.
In situ hybridization was used to study the expression of members of the nerve growth factor family of trophic factors in rat hippocampus following stimulation of afferent cholinergic and glutamatergic pathways with quisqualate. A transient increase in brain-derived neurotrophic factor (BDNF) and beta-nerve growth factor (NGF) mRNA expression in the hippocampus was seen 4 h after a quisqualate injection into the medial septal nucleus. Both BDNF and NGF mRNA levels increased more than 4-fold in the granule layer of the dentate gyrus and for BDNF mRNA also in the pyramidal cells of CA1, while the levels of BDNF mRNA in CA3 increased 2-fold. The increase in BDNF and NGF mRNA levels were completely prevented by pretreatment with systemic injections of either scopolamine or diazepam. A quisqualate injection into the entorhinal cortex, containing glutamatergic afferents to the hippocampus, resulted in a 15-, 5- and 17-fold increase in the expression of BDNF mRNA in the ipsilateral granule cells, CA3 and CA1 pyramidal cells, respectively. Similar increases were also seen in the hippocampus contralateral to the injections. In contrast, the level of NGF mRNA did not increase significantly in any of the subfields in the hippocampus. The increase in BDNF mRNA after cortex injections was attenuated by diazepam but not by scopolamine. These findings imply that increased activity in afferent cholinergic and glutamatergic pathways to the hippocampus differentially regulate expression of the NGF family of neurotrophic factors in the hippocampus.
运用原位杂交技术，研究了在使用喹啉酸刺激传入胆碱能和谷氨酸能通路后，大鼠海马中神经营养因子神经生长因子家族成员的表达情况。向内侧隔核注射喹啉酸4小时后，可见海马中脑源性神经营养因子（BDNF）和β-神经生长因子（NGF）mRNA表达出现短暂增加。在齿状回颗粒层中，BDNF和NGF的mRNA水平均增加了4倍以上，CA1锥体细胞中的BDNF mRNA水平也有所增加，而CA3中BDNF mRNA水平增加了2倍。全身注射东莨菪碱或地西泮预处理可完全阻止BDNF和NGF mRNA水平的升高。向含有海马谷氨酸能传入纤维的内嗅皮质注射喹啉酸，导致同侧颗粒细胞、CA3和CA1锥体细胞中BDNF mRNA表达分别增加15倍、5倍和17倍。注射对侧海马也出现了类似的增加。相比之下，海马中任何亚区的NGF mRNA水平均未显著增加。皮质注射后BDNF mRNA的增加可被地西泮减弱，但不能被东莨菪碱减弱。这些发现表明，传入海马的胆碱能和谷氨酸能通路活性增加对海马中神经生长因子家族的神经营养因子表达具有不同的调节作用。
