Brain-derived neurotrophic factor and Glial cell line-derived neurotrophic factor expressions in the trigeminal root entry zone and trigeminal ganglion neurons of a trigeminal neuralgia rat model.

Microvascular compression on the trigeminal root entry zone (TREZ) is the main etiology of trigeminal neuralgia (TN) patients. To investigate brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) in the trigeminal ganglion (TG) and TREZ, immunofluorescence staining and Western blot were used in a rat TN model. Both BDNF and GDNF were observed in the TG neurons and TREZ. The expression of the BDNF dimer in the TG was increased in the TN group, while GDNF expression was decreased after compression injury. The BDNF dimer/pro-BDNF ratio in the TREZ of the TN group was higher than that in the sham group, but the GDNF expression in the TREZ was significantly lower than that in the sham group. These results suggested that compression injury in the TREZ of rats induced dynamic changes in BDNF and GDNF in both the TG and TREZ, and these changes are involved in the nociceptive transmission of the TN animal model.