Sansho Intake Modulates Ileum Activity in Stress-loaded Rats

Sansho (Japanese pepper) is a common spice widely used in Japanese cuisine. In addition, it is also an important component in Kampo medicine, such as in Daiken Chuto, which stimulates gastrointestinal motility and improves postoperative ileus. On the other hand, we previously reported that gravity stress loading produce negative effects on ileal movements. In the present study, we report changes in ileal motility after gravity-stress with and without Sansho intake in male and female rats. Ileal movements were activated by topical Acetylcholine (Ach) application, and maximum amplitudes (MA) of the evoked contraction were compared. Clear tonic patterns were observed in the ileal motility after Ach application. After short-term stress, there were no significant differences in MA between control and Sansho-intake groups in both sexes. However, after long-term stress-loading, significant enhancement of MA was observed in Sansho-intake group in males, but not in females. The present study showed that SAN affected Ach-induced ileal motility in the male, but not in the female after long-term stress loading, indicating sex differences in effects of Sansho intake. It is suggested that Sansho is more effective in males than in females to decrease negative stress response.