The bi-phased course of electrophysiological response of isolated snail intestine on mechanical stimulation.

The transepithelial potential difference and changes of diameter of isolated snail intestine as index of its motility were studied in immersed bath in control conditions and after gentle stimulation by 60 seconds of washing of the intestinal lumen. Immediate depolarization and 20% augmentation of the lumen were observed during the stimulation. After stimulation, additional transient depolarization of the transepithelial potential difference and gradual diminution of intestine lumen back to control values over a period of 20 minutes occurred. The immediate reaction was greatly influenced by the presence of sodium or chloride ion transport inhibitors, however, the late phase of the response was not. It is hypothesized that changes of transepithelial electrogenic ion transport and of intestinal motility during the stimulation mirror the inflow of intestinal content and after completion of stimulation may be related to its storage.