Methods: 9 Sprague-Dawley rats were anesthetized using 5% isoflurane induction followed by maintenance with 3% isoflurane. Rats were divided into three equal groups. Each group received injections of either 5%, 10%, or 15% mustard oil solution into the maxillary left vestibule adjacent to the second maxillary molar. Control rats were selected from each group at random and were provided access to 200g DMSO and tap water solution ad libitum. Experimental rats were provided with 100 µM of AP18 in 200g DMSO and water solution ad libitum. Objective water drinking behaviors and subjective behavioral and inflammatory symptom analyses were recorded over a one week period post-mustard oil injections.
Results: Rats provided with access to TRPA1 antagonist, AP18, experienced a reduction of inflammation and return to baseline behaviors at a faster rate than rats provided with tap water and DMSO alone. Rats provided with TRPA1 immediately following mustard oil injections experienced a reduction in inflammation and return to baseline activity levels 24 hours post-mustard oil injection. Control rats remained mildy inflamed and lethargic past day three post-mustard oil injections.
Conclusions: AP18 may have potential as a therapeutic alternative to commonly prescribed drugs that are associated with adverse side effects such as addiction and liver damage. Further examination may reveal that AP18 has potential to reduce inflammatory responses if administered pre-operatively or intra-operatively.
**This study represents a pilot study during which effective concentrations of mustard oil and AP18 were established. The experiment uses repeatable techniques that may be referenced and utilized for future examination of AP18.