Objective: To investigate the regulation of P2X3 mRNA expression in the trigeminal ganglion sensory neurons after the nociceptive stimulation by orthodontic tooth movement force.
Methods: Male Sprague-Dawley rats weighing 200-250 g were used. The mimic tooth movement appliance was used in the rats of the experiment group. The rats were sacrificed after 4 h, 12 h, 1 d, 2 d, 3 d, 5 d and 7 d after experiment. The expression of P2X3 mRNA was detected by in situ hybridization with an oligonucleotide probe.
Results: After force was given to the teeth of rats, the number of P2X3 mRNA positive neurons increased on the first day and reached the peak on the third day; then, the level of P2X3 mRNA expression began to decrease, and after seven days, it returned to the level of the control group.
Conclusion: The results suggest that the P2X3 mRNA expression is transiently upregulated and anterogradely transported in trigeminal primary sensory neurons after orthodontic tooth movement and that P2X3 receptor may play a role in the pathomechanism of nociception in primary sensory neurons during orthodontic treatment.