FIGURE 8.

Effect of celastrol on TDI-induced nasal symptoms and up-regulation of H1R and IL-4 gene expression in TDI-sensitized rats. Rats were sensitized with 10 μl of 10% TDI in ethyl acetate for 2 weeks. After a 1-week interval, provocation was performed with 10 μl of 10% TDI. The control group was sensitized with only ethyl acetate. Celastrol (1 mg/kg) were administered once a day for 1 week. Celastrol was administered 1 h before TDI application when rats were sensitized with TDI. A, the number of sneezes was counted during the 10-min period just after TDI provocation. B, nasal scores (degrees of swelling and redness and watery rhinorrhea) were scored according to the criteria listed in Table 2 on a scale ranging from 0 to 3. Nasal mucosa samples were collected 4 h after TDI provocation, and total RNA was isolated. H1R (C) and IL-4 (D) mRNA levels were determined by real-time quantitative RT-PCR. Data are presented as the mean ± S.E. (error bars) (n = 4). **, p < 0.01; *, p < 0.05 versus TDI.