Objective: To investigate the sensory and sympathetic innervations associated with both acupoint “Shenshu” (BL23) and kidney in the rat for insight into the neuronal correlation between the Back-Shu Point and its corresponding visceral organ.

Methods: The BL23 and kidney were selected as the representative acupoint and visceral organ in this study, in which their local nerve fibers were examined by using double fluorescent immunohistochemistry with calcitonin gene-related peptide (CGRP) and tyrosine hydroxylase (TH). Meanwhile, their neuronal correlation in the dorsal root ganglia (DRGs), spinal cord, and sympathetic (paravertebral) chain were investigated using a double fluorescent neural tracing technique with Alexa Fluor 488 and 594 conjugates with cholera toxin subunit B (AF488/594-CTB).

Results: The local tissue of acupoint BL23 and the fibrous capsule of kidney distributed abundantly with CGRP- and TH-positive nerve fibers, corresponding to their sensory and sympathetic innervation. On the other hand, the sensory neurons associated with acupoint BL23 and kidney were labeled with AF488/594-CTB and distributed from thoracic (T) 11 to lumbar (L) 3 DRGs and from T10 to L2 DRGs, respectively, in which some of them in T12-T13 DRGs were simultaneously labeled with both AF488/594-CTB. Also, postganglionic neurons associated with both acupoint BL23 and kidney were found in the sympathetic chain at the same spinal segments but separately labeled with AF488-CTB and AF594-CTB.

Conclusion: Our study demonstrates the neural characteristics of the acupoint BL23 and kidney in the rat from the perspective of neurochemistry and neural pathways, providing an example for understanding the neuronal correlation between the Back-Shu Points and their corresponding visceral organs. These results suggest that the stimulation of the Back-Shu Points may regulate the activities of the target-organs via the periphery sensory and sympathetic pathways.

目的：调查与穴位“ Shenshu”（BL23）和大鼠肾脏相关的感觉和交感神经，以了解Back-Shu点及其对应的内脏器官之间的神经元相关性。

方法：选择BL23和肾脏作为本研究的代表性穴位和内脏器官，通过降钙素基因相关肽（CGRP）和酪氨酸羟化酶（TH）的双重荧光免疫组织化学检查其局部神经纤维。同时，使用Alexa Fluor 488和594结合物与霍乱毒素亚基B（AF488 / 594-CTB）的双重荧光神经示踪技术，研究了它们在背根神经节（DRGs），脊髓和交感（椎旁）链中的神经元相关性。 ）。

结果：穴位BL23的局部组织和肾脏的纤维囊分布有丰富的CGRP和TH阳性神经纤维，对应于它们的感觉和交感神经。另一方面，与穴位BL23和肾脏相关的感觉神经元被AF488 / 594-CTB标记，分别从胸（T）11到腰（L）3 DRG和T10到L2 DRG分布，其中一些它们在T12-T13 DRG中同时用AF488 / 594-CTB标记。同样，在交感神经链中相同的脊髓节段发现了与穴位BL23和肾脏相关的神经节后神经元，但分别用AF488-CTB和AF594-CTB标记。

结论：我们的研究从神经化学和神经通路的角度论证了大鼠穴位BL23和肾脏的神经特征，为理解Back-Shu点及其相应内脏器官之间的神经元相关性提供了一个实例。这些结果表明对Back-Shu点的刺激可能会调节靶器官的活动。通过 周围的感觉和交感途径。