Scutellariae Radix enhances but Scutellariae Radix-containing Kampo formulas, Orengedokuto and San'oshashinto, prevent intestinal bleeding associated with indomethacin-induced enteropathy in mice

A single subcutaneous injection of indomethacin (INDO) in mice induced enteropathy characterized as ulceration in small intestine, which was associated with the elevation of fecal hemoglobin (Hb) content and the decrease in Hb and total protein concentration in blood. Oral administration of Scutellariae Radix (SR) (500 mg/kg) enhanced fecal Hb excretion but did not affect the decrease in blood Hb and total protein concentration in INDO-treated mice. In contrast, administration of two SR-containing kampo formulas, Orengedokuto (OGT) and San'oshashinto (SST) at 1100 mg/kg, which contained nearly the same amounts of baicalin as SR extracts at 500 mg/kg, markedly suppressed INDO-induced intestinal bleeding and blood loss. Plasma INDO concentration was not changed by the administration of SR, OGT or SST. The present study suggests that OGT and SST are useful for limiting complications such as intestinal bleeding and blood loss associated with INDO-induced enteropathy. However, possible harmful effects of other SR-containing kampo formulas on INDO-induced enteropathy remain to be investigated.