Abstract: Objective: To investigate the dynamic expression of GFAP in the trigeminal ganglion (TG), and to elucidate the potential role of activated SGCs in the trigeminal nervous system that involved in the development of pulpitis and associated hyperalgesia. Methods: A rat animal-model with pulpitis was induced by performing CFA on Sprague-Dawley rats. The dynamic expression of GFAP in TG was demonstrated by immunofluorescence, and the mRNA of GFAP was detected by semi-quantitative reverse transcription PCR. Results: The GFAP-positive cells were found to present a typical morphology of circle that surrounded the neurons in TG after 24 hours post CFA-inflammation. Results of semi-quantitative RT-PCR showed that the mRNA of GFAP was increased significantly and reached the peak at 24 hours post CFA-inflammation compared to the control. Conclusion: The trigeminal nervous system may participate in the histopathological development of pulpitis and hyperalgesia with the activation of SGCs.

Key words: Pulpitis , GFAP, SGCs, Hyperalgesia