Pharmacological studies of anti-diarrhoeal activity of Gentianopsis paludosa

The pharmacological studies of anti-diarrhoeal activity of Gentianopsis paludosa were carried out. The 75% ethanol extract (100–400 mg/kg) of Gentianopsis paludosa inhibited castor oil-induced diarrhoea and also reduced gastrointestinal motility in the charcoal meal test in mice. In the rabbit-isolated ileum, the extract showed inhibitory effects not only on its spontaneous contraction, but also on acetylcholine (Ach, 0.1 mM)- and KCl (60 mM)-induced contractions. Furthermore, the ethanol extract (0.4–0.6 mg/ml) shifted the CaCl2 dose–effect curves to the right in a non-competitive manner and significantly reduced the acetylcholine-induced contraction of isolated ileum in Ca2+-free solution like verapamil (0.1 mM), which suggest that the extract interferes with Ca2+ movement. These results support the traditional use of Gentianopsis paludosa in the treatment of diarrhoea.