The relationship between motor activity and transmural potential difference in the guinea pig intestine in vitro: is there a neural link?

The aim of the experiments was to examine, in vitro, the role of the enteric nervous system in the relationship between motor activity and transmural potential difference (PD) in the guinea pig jejunum and colon using the nerve blocking agents tetrodotoxin (TTX) and aconitine. Histological data showed that perfusion of the intestinal segments with gassed Hepes solution was essential for the maintenance of transmural PD. Disruption of the mucosa was associated with a loss of spontaneous fluctuations in transmural PD without any loss of spontaneous motor activity. Under spontaneous conditions, a neural pathway exists linking jejunal and colonic motility with transmural PD. However, in some cases a mechanical link was also apparent, as an attenuated TTX and aconitine-resistant component.