Effects of Ginsenoside Total Saponins on Experimental Irritable Bowel Syndrome in Rats

In the previous study, we reported that the in viかo inhibitory effect of ginsenosides, active ingredient of Panax ginseng, on $5-HT_{3A}$ receptor channel activity is coupled to in vivo anti-vomiting and anti-nausea effect. In the present study, we further investigated that the inhibitory effect of ginsenosides, active ingredient of Panax ginseng, on 5-HT3A receptor channel activity is also coupled to attenuation of irritable bowel syndrome (IBS), which is induced by colorectal distention (CRD) and $0.6\%$ acetic acid treatment. The CRD-induced visceral pains induced by CRD and acetic acid treatment are measured by frequency of contractions of the external oblique muscle in conscious rats. Treatment of GTS significantly inhibited CRD-induced visceral pain with dose-dependent manner. The $EC_{50}$ was $5.5{\pm}4.7$ mg/kg ($95\%$ confidence intervals: 1.2-15.7) and the antinociceptive effect of GTS on visceral pain was persistent for 4 h. We also compared the effects of protopanaxadiol (PD) ginsenosides and protopanaxatriol (PT) ginsenosides with saline on acetic acid-and CRD-induced visceral pain, and found that protopanaxatriol (PT) ginsenosides was much more potent than PD ginsenosides in attenuating CRD-induced visceral pain. These results indicate that U ginsenosides of Panax ginseng are components far attenuation of experimentally CRD-induced visceral pains.