Gene expression change of OGR1 family genes after peripheral inflammation. The wild-type CD1 mice (8–12 week-old) were injected at right hind paws with 25 μl of capsaicin (100 μg/ml in saline containing 10% ethanol and 0.5% Tween 80, A), carrageenan (20 mg/ml, B), CFA (50% in saline, C), or saline (D). At 4, 24, and 72 hours after injection, the mice were killed. Lumbar 4–6 DRG ipsilateral and contralateral to injected paws were taken for RNA extraction for quantitative RT-PCR. The contralateral DRG was used as untreated controls. The expression of each gene on the ipsilateral DRG was first normalized to that of mGAPDH and then represented as a relative value to contralateral controls. All data are presented as mean ± SEM of quadruplicates of three experiments (N = 3, n = 3 mice). Comparison between inflammatory agent-injected and saline-injected animals was by t test. *p < 0.05, **p < 0.01, ***p < 0.001.