成年大鼠基底前脑隔-斜角带复合体的巢蛋白免疫阳性神经元至海马的纤维投射

目的 观察大鼠基底前脑巢蛋白(nestin)免疫阳性神经元的纤维投射。方法 先用荧光素逆行追踪法显示基底前脑内投射至海马的荧光素标记神经元，观察摄片后再进行nestin免疫组织化学染色。对比荧光照片和免疫组织化学染色照片，辨认荧光素和nestin双标神经元。结果 在基底前脑注射侧的内侧隔核(MS)和斜角带核的垂直支(vDB)和水平支(hDB)均存在荧光素标记细胞，其中一部分为nestin免疫阳性。在MS、vDB和hDB，双标细胞占逆行标记细胞的比例分别为21．3％、25％和20．6％；占nestin阳性细胞的比例分别为26．6％、15．7％和16．3％。结论 大鼠基底前脑的nestin免疫阳性神经元发出神经纤维向海马投射。提示在基底前脑有一个平行于隔-海马胆碱能投射和GABA能投射的第3条通路。

THE PROJECTION OF NESTIN IMMUNOREACTIVE NEURONS TO HIPPOCAMPUS WITHIN THE MEDIAL SEPTUM AND DIAGONAL BAND COMPLEX OF BASAL FOREBRAIN IN THE ADULT RAT

Objective To observe the projection of nestin immunoreactive neurons in the basal forebrain of rat. Methods The retrograde fluorescent tracing method was used and the sections containing basal forebrain were observed and photographed. Then Nestin immunohistochemical staining was made on those same sections. The fluorescein/nestin double labeled neurons were determined by comparing the fluorescent photographs with the nestin immunohistochemical staining photographs. Results Many fluorescent labeled cells were found in the ipsilateral medial septum(MS), the vertical limb of the diagonal band(vDB) and the horizontal limb of the diagonal band(hDB), some of which were nestin immunoreactive. In MS, vDB and hDB double labeled neurons accounted for 21 3%, 25% and 20 6% of the retrogradely labeled neurons and for 26 6%, 15 7% and 16 3% of the nestin immunoreactive neurons.Conclusion The nestin immunoreactive neurons in the basal forebrain of rat give off fibers projecting to hippocampus. It is suggested that there is a third projecting pathway from basal forebrain to hippocampus, which parallel with the cholinergic and GABAergic septum hippocampus pathways.