Abstract:

Objective   To explore the pathogenesis of trigeminal neuralgia by establishing a rat model of trigeminal neuralgia and measuring changes of SP and β-EP in hypothalamus and hypophysis. Methods   Twenty-eight male adult Sprague-Dawley rats were randomly assigned to the experimental group(Group A), the Sodium Chloride group(Group B) and the control group(Group C). In Group A, the rats were injected with 3μL penicillin G-K into the subarchnoid space caudal to obex. After the models were established, they were killed, and then their hypothalamus and hypophysis were taken out and were determined for the concentrations of SP and β-EP by radioimmunological assay(RIA) . As to Group B, the progress was the same as Group A except that the rats were injected with 3μL Sodium Chloride and were killed 30 minutes later. And the rats in Group C were directly killed, others just following Group A. Results   The concentration of SP in the experimental group was significantly higher than that in the Sodium Chloride group and the control group (P<0.01)，while the concentration of β-EP was much lower(P<0.01) but there was no considerable difference between the Sodium Chloride group and the control group (P>0.05).  Conclusion   Neuropeptides, such as SP and β-EP, may play important roles in the pathphysiological mechanism of trigeminal neuralgia.

Key words: Trigeminal neuralgia； Neuropeptides； Substance P； beta-Endorphin