Panoramic and local histological observations of biotinylated dextran amine neural tracer labeling in the motor cortex of rat brain
10.3969/j.issn.1006-7795.2025.01.014
- VernacularTitle:大鼠大脑皮层运动区生物素化葡聚糖胺神经示踪标记的全景和局部组织学观察
- Author:
Jiaying LU
1
;
Dongsheng XU
1
;
Jingjing CUI
1
;
Yuqing WANG
1
;
Yuxin SU
1
;
Yihan LIU
1
;
Jia WANG
1
;
Wanzhu BAI
1
Author Information
1. 中国中医科学院针灸研究所腧穴结构研究室,北京 100700
- Publication Type:Journal Article
- Keywords:
motor cortex;
neural circuits;
corticospinal tract;
panoramic scanning;
microscopic imaging;
three-dimensional reconstruction
- From:
Journal of Capital Medical University
2025;46(1):83-90
- CountryChina
- Language:Chinese
-
Abstract:
Objective To reveal the detailed histological characteristics of pyramidal neuron cell bodies and their axonal projections along the corticospinal tract in the primary motor cortex(M1)of the brain,by using the biotinylated dextran amine(BDA)neural tracing technique combined with panoramic and local microscopic imaging technologies.Methods A total of 100 nL of 10％BDA(10,000 molecular weight)was injected into M1 region using stereotaxic system.The distribution of BDA labeling along the corticospinal tract was continuously tracked with panoramic tissue scanning analysis system.Detailed observations of the histological characteristics of BDA labeling were carried out with laser confocal microscope.Results It is more convenient to observe the overall distribution of BDA neural labeling by using the panoramic tissue scanning analysis system.Around the injection site in M1,the BDA labeling was shown in the somas of pyramidal neurons in layer V.In the M1 region corresponding to the contralateral site of the injection site and ipsilateral primary sensory cortex,BDA showed predominantly the anterograde labeled nerve fibers accompanied by a few retrograde labeled neurons.Besides,BDA labeled nerve fibers-including bundles and terminals-projecting to regions such as the ipsilateral striatum,thalamus,internal capsule,cerebral peduncle,and pons,and further reaching the contralateral spinal cord via the brainstem pyramidal decussation.Confocal microscopy and its 3D reconstruction system facilitated detailed analysis of the local microscopic features of BDA labeling,revealing retrograde labeled neuron cell bodies,dendrites and their spines,as well as anterograde labeled nerve fibers and their terminals.Conclusions These findings demonstrated that the integration of traditional BDA neural tracing with panoramic tissue scanning analysis and confocal microscopy provided an effective approach to the observation and analysis of long-projection neural circuits from panoramic to local perspectives,with broad application prospects.
