Effects of TXYF on colon hypersensitivity. (a) The effect of TXYF on AWR score in PI-IBS rats. Abdominal withdrawal reflex score (AWR score) measured in response to graded colorectal distension shows significant differences between the PI-IBS group and the normal group and between TXYF treatment group and the PI-IBS group at 40 mm Hg. Data are mean ± S.D. *P < 0.05 vs. Normal, #P < 0.05 vs. PI-IBS. (b) The effect of TXYF on PTP in PI-IBS rats. Pain threshold pressure (PTP) measured showed significant decrease in the rats with visceral hypersensitivity comparing to the normal control group, and a significant increase in the TXYF at three dosage treatment group comparing to the PI-IBS group. Data are mean ± S.D. **P < 0.01 vs. Normal, #P < 0.05 vs. PI-IBS.