Progesterone Attenuates Allodynia of Inflamed Temporomandibular Joint through Modulating Voltage-Gated Sodium Channel 1.7 in Trigeminal Ganglion

Figure 1

Progesterone dose dependently attenuated sensitivity of TMJ nociception and downregulated Nav1.7 expression in TG. (a) Confirmation of the effectiveness of ovariectomized and P4 replacement in rats. Serum levels of P4 in the ovariectomized groups treated with 0 μg, 350 μg, or 700 μg P4 increased dose dependently. (b) Head withdrawal threshold. The lower the head withdrawal thresholds, the more sensitive the TMJ nociception will be. The head withdrawal threshold was increased by P4 application, suggesting that the sensitivity of TMJ nociception was decreased. (c) Real-time PCR analysis for Nav1.7 expression in TG. P4 increased the mRNA expression of Nav1.7 in TG. (d) Representative immunoblotting for Nav1.7 expression in TG after estrogen replacement. β-Actin served as an internal control for equal loading. versus the control group; versus the 0 μg group; versus the 350 μg P4 group. Data are expressed as mean ± SD.

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