Ion transport in the colon of rats experimentally infected with liver fluke (Fasciola hepatica).

The effect of liver fluke infection (Fasciola hepatica) on ion transport in the rat proximal colon was evaluated with electrophysiological methods using an Ussing apparatus. Rats were orally infected with F. hepatica metacercariae. The experimental groups of rats at 4 weeks post-infection (wpi) were in the acute stage of fasciolosis, while those at 7, 10 and 13 wpi represented the chronic phase of liver fluke infection. The control group comprised uninfected rats. The experiment consisted of recording transepithelial electrical potential difference (PD) and transepithelial electrical resistance (R) in the colon of the rats. The results revealed reduced PD levels in the colon of rats, especially during the acute phase of fasciolosis. During its chronic phase, a gradual growth in the intestinal transepithelial potential difference was found. Rat fasciolosis did not cause changes in colon sensitivity to mechanical stimulation or in the value of electrical resistance. Only at 13 wpi was resistance found to have dropped. The results have demonstrated that experimental fasciolosis leads to activation of inflammatory mediators and thus to stimulation of nerve fibres, which modifies ion transport in the epithelium of the host large intestine.