Establishing a Mouse Model of Chlorpromazine-Induced Corneal Trigeminal Denervation

PURPOSE: This study aimed to establish a mouse model of chlorpromazine-induced corneal trigeminal denervation (CCTD). METHODS: Retrobulbar chlorpromazine injections were administered to 6- to 8-week-old C57BL/6j mice to induce corneal denervation. Additionally, apoptosis was assessed in isolated primary trigeminal ganglion cells after culturing in a conditioned medium containing chlorpromazine. Finally, the success rate of model generation, mortality and complication rates, and model-preparation learning curves were compared between the CCTD model and the electrocoagulation and axotomy models. RESULTS: Chlorpromazine retrobulbar injections resulted in trigeminal denervation, leading to a reduced blink reflex, corneal nerve density, and corneal epithelium thickness. Furthermore, 90% (9/10) of the mice developed epithelial defects, accompanied by increased apoptosis and inhibited proliferation of corneal epithelial cells. In vitro, trigeminal ganglion cell apoptosis increased after culturing in a conditioned medium containing chlorpromazine. Moreover, the CCTD model exhibited a higher success rate, longer survival rate, and lower complication rate compared to the electrocoagulation and axotomy models. Crucially, the learning curve demonstrated that the method used to generate the CCTD model was easy to learn. CONCLUSIONS: The CCTD model is a user-friendly mouse model for studying corneal trigeminal denervation that offers a less invasive alternative to existing models. TRANSLATIONAL RELEVANCE: The CCTD model serves as a valuable tool for investigating the functional mechanisms of corneal trigeminal nerves and their interactions with corneal cells.