Eriksdotter-Nilsson M, Skirboll S, Ebendal T, Hersh L, Grassi J, Massoulié J, Olson L
Department of Histology and Neurobiology, Karolinska Institute, Stockholm, Sweden.
Exp Brain Res. 1989;74(1):89-98. doi: 10.1007/BF00248282.
The effects of nerve growth factor (NGF) on developing central cholinergic neurons were studied using intraocular grafts of rat fetal (E17) basal forebrain tissue. Prior to grafting, grafts were incubated in NGF or saline. Transplants were allowed to mature for six weeks, receiving weekly intraocular injections of NGF or saline. Measurements of NGF levels in oculo after one single injection showed that NGF slowly decreases in the anterior chamber fluid, and after one week, low but significant levels were still present in the eye. Following pretreatment with diisopropylfluorophosphate (DFP), the cholinergic neurons in the grafts were analyzed using three morphological markers: antibodies to cholineacetyltransferase (ChAT), antibodies to acetylcholinesterase (AChE Ab) and acetylcholinesterase histochemistry (AChE). The transplants grew well and became vascularized within the first week. The growth of the NGF-treated basal forebrain grafts was significantly enhanced as compared to the growth of the saline-treated grafts evaluated with repeated stereomicroscopical observations directly through the cornea of the ether-anaesthetized hosts. The NGF-treated grafts contained almost twice as many cholinergic neurons seen with all the cholinergic markers used, as the saline-treated grafts. However, there was no difference in cholinergic cell density between the two groups. The morphology and size of an individual cholinergic neuron was similar in the two groups. The fiber density as evaluated with AChE-immunohistochemistry did not change after NGF-treatment. The DFP-treatment did not seem to affect the AChE-immunoreactivity since an extensive fiber network was found, whereas almost no fibers were seen using conventional AChE histochemistry. We have demonstrated that in oculo transplantation of basal forebrain is a useful model for examining in vivo effects of NGF on central cholinergic function. The marked volume increase of NGF-treated grafts and the unchanged density of cholinergic cells and terminals suggests, that NGF increases the survival of not only developing cholinergic neurons, but possibly other non-cholinergic neurons and non-neuronal cells as well. These results support the notion that NGF acts as a neurotrophic factor on cholinergic and possibly non-cholinergic cells in the central nervous system.
利用大鼠胚胎（E17）基底前脑组织的眼内移植，研究了神经生长因子（NGF）对发育中的中枢胆碱能神经元的影响。在移植前，将移植物在NGF或盐水中孵育。移植后让其成熟六周，每周进行一次眼内注射NGF或盐水。单次注射后眼内NGF水平的测量表明，前房液中的NGF缓慢下降，一周后，眼中仍存在低但显著的水平。在用二异丙基氟磷酸酯（DFP）预处理后，使用三种形态学标记物分析移植物中的胆碱能神经元：抗胆碱乙酰转移酶（ChAT）抗体、抗乙酰胆碱酯酶（AChE Ab）抗体和乙酰胆碱酯酶组织化学（AChE）。移植物生长良好，并在第一周内血管化。与通过乙醚麻醉宿主的角膜直接进行反复立体显微镜观察评估的盐水处理移植物的生长相比，NGF处理的基底前脑移植物的生长显著增强。使用所有胆碱能标记物观察到，NGF处理的移植物中胆碱能神经元的数量几乎是盐水处理移植物的两倍。然而，两组之间胆碱能细胞密度没有差异。两组中单个胆碱能神经元的形态和大小相似。用AChE免疫组织化学评估的纤维密度在NGF处理后没有变化。DFP处理似乎不影响AChE免疫反应性，因为发现了广泛的纤维网络（使用传统AChE组织化学几乎看不到纤维）。我们已经证明，基底前脑的眼内移植是一种用于研究NGF对中枢胆碱能功能体内作用的有用模型。NGF处理的移植物明显的体积增加以及胆碱能细胞和终末密度不变表明，NGF不仅增加了发育中的胆碱能神经元的存活，还可能增加了其他非胆碱能神经元和非神经元细胞的存活。这些结果支持了NGF在中枢神经系统中对胆碱能以及可能的非胆碱能细胞起神经营养因子作用的观点。
