Antisecretory (antidiarrhoeal) activity of Indian medicinal plants against Escherichia coli enterotoxin-induced secretion in rabbit and guinea pig ileal loop models.
Alcohol, hexane, chloroform, butanol and aqueous extracts of different parts of 31 indigenous medicinal plants of India (traditionally used to treat diarrhoea) were screened for their antisecretory activity against E. coli heat labile (LT), heat stable (ST) and LT/ST enterotoxin-induced secretory responses in rabbit and guinea-pig ileal loop models. The alcohol extracts (300 mg) of Andrographis paniculata (whole plant) and Coleus forskohlii roots inhibited fluid accumulation induced by LT, ST and LT/ST toxins by 82.2, 71.8 and 80.8%, and by 72.2, 84 and 87.8%, respectively. Eclipta alba (aerial parts), Tridex [Tridax] procumbens (aerial parts), Cassia fistula (seeds), Papaver somniferum (seeds), Myristica fragrans (seeds and flowers) and Litsea glutinosa (bark) extracts also exhibited antisecretory activity. Coleonol (forskolin), was isolated from the C. forskohlii extract, and the antisecretory activities of 2 active principles of coleonol (coleosial-A and coleonol-B) were similar to that induced by the antidiarrhoeal drug, loperamide.