Effect of a peripheral NMDA receptor antagonist on glutamate-evoked masseter muscle pain and mechanical sensitization in women

摘要: Aims: To test the hypothesis that local injection of N-methyl-D-aspartate (NMDA) receptor antagonist ketamine would significantly attenuate glutamate-evoked masseter mechanical sensitization and muscle pain in healthy young women either taking oral contraceptives (W+OC) or not (W-OC). Methods: Experimental was evoked 47 female subjects (W+OC, n = 25; W-OC, 22) by 2 injections glutamate (0.2 mL, 1 mol/L) into muscle. A first alone followed a second injection, 35 minutes later, combined with (0, 1, 10 mmol/L). Evoked intensity scored on 10-cm electronic visual analog scale (VAS). Distribution perceived drawn lateral view face (pain drawing). Masseter pressure thresholds (PPT) pressure-pain tolerances (PPTOL) were determined bilaterally before at regular time intervals after injections. Analyses variance (ANOVA) used to data. Results: There no main effects any VAS parameters drawing (ANOVAs: P > .055). Furthermore, there differences PPT, PPTOL, peak pain, duration, overall when W-OC compared W+OC .087). Repeated decreased PPT PPTOL < .001); however, this effect attenuated ketamine. Conclusions: Peripherally administered had women, which contrasts recent observations men. Further studies will be needed reveal mechanisms underlie apparent sex-related difference ketamine-mediated analgesia.