Management of trigeminal neuralgia in a rat model using intranasal administration of Bulleyaconitine A.

Introduction: Trigeminal neuralgia (TN), characterized by severe facial pain triggered by mild stimuli, is challenging to treat effectively and non-invasively. Traditional treatments, including microvascular decompression and medications like carbamazepine, have limitations. This study investigates the potential of Bulleyaconitine A (BAA), an alkaloid that selectively inhibits specific sodium channels, for managing TN in a rat model via intranasal administration.

Method: Adult male Sprague-Dawley rats were subjected to a Chronic Constriction Injury (CCI) of the distal infraorbital nerve to model trigeminal neuralgia (TN). BAA was administered intranasally, and pain thresholds were assessed using the von Frey filament stimulation technique. Comparative analyses involved transnasal carbamazepine administration, with a focus on optimizing BAA dosage and delivery methods, including nasal drops, gavage, and subcutaneous injection.

Result: Intranasal BAA significantly increased pain thresholds in TN rats, demonstrating superior performance compared to the control group and achieving efficacy comparable to carbamazepine over a two-week period. Among various administration routes evaluated, nasal delivery was identified as the most effective.

Discussion: The study shows BAA's superior efficacy compared to carbamazepine, highlighting its potential as a TTX-selective sodium channel blocker for TN. Intranasal BAA administration offers a novel, non-invasive therapeutic option. Further research on dosage forms for clinical use, such as drug-encapsulating nanoparticles or vesicles for targeted delivery in neurological disorders, is warranted.