Bilateral transport of neuronal tracer after unilateral administration: Investigation of potential peripheral mechanism.
Jaime Fabillar, Lutfi Putra Perdana, Swarnalakshmi Raman, Junhel Dalanon, Masamitsu Oshima, Otto Baba, Yoshizo Matsuka
Author Information
Jaime Fabillar: Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan.
Lutfi Putra Perdana: Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan.
Swarnalakshmi Raman: Department of Neural and Pain Sciences, School of Dentistry, University of Maryland Baltimore, MD 21201, United States.
Junhel Dalanon: Medical Sciences Division, DOST National Research Council of the Philippines, Taguig 1631, Philippines.
Masamitsu Oshima: Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan.
Otto Baba: Department of Oral and Maxillofacial Anatomy, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan.
Yoshizo Matsuka: Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan. Electronic address: matsuka@tokushima-u.ac.jp.
Previous studies have shown pain attenuation after the administration of botulinum neurotoxin type A into the whisker pad contralateral to the nerve injury. It further showed localization in the neurons of the bilateral trigeminal ganglia, indicating a possible connection between the trigeminal nerves. Thus, this study aimed to investigate the potential link between the right and left trigeminal ganglia, considering their anatomical proximity and the possible neural interactions between these structures. The fluorogold (FG) neuronal tracer was localized in the neurons of both the right and left trigeminal ganglia (TG) after unilateral injection into the whisker pad. In contrast, there was a substantial decrease in FG localization in the contralateral ganglion following colchicine (CCh) administration or after midline incision surgery. Moreover, FG injected directly into the trigeminal ganglion was exclusively localized on the ipsilateral side. Additionally, systemic administration of FG revealed its localization not only within the bilateral TG neurons but also in the bilateral dorsal root ganglia (DRG) neurons, mirroring the findings following whisker pad injection. These findings suggest that bilateral transport of fluorogold occurs at the peripheral level, possibly through its diffusion from the injection site to the contralateral whisker pad and/or nerve axonal crossover through the midline. Further studies are required to clarify the specific peripheral pathways and explore the bilateral nerve connections.
