Contribution of active membrane processes to conducted hyperpolarization in arterioles of hamster cheek pouch.

Objective: Conduction of vasodilation triggered by acetylcholine (ACh) in arteriolar networks reflects hyperpolarization and its spread from cell to cell along the vessel wall. The amplitude and distance of the vasomotor response appear greater than can be explained by simple passive decay of the electrical signal. The authors tested the hypothesis that the conduction of hyperpolarization involves active membrane processes as the signal travels along the arteriolar wall.

The possum sphincter of Oddi pumps or resists flow depending on common bile duct pressure: a multilumen manometry study.

The sphincter of Oddi (SO) regulates trans-sphincteric flow (TSF) by acting primarily as a pump or as a resistor in specific species. We used the Australian possum SO, which functions similarly to the human SO, to characterize SO motility responses to different common bile duct (CBD) and duodenal pressures. Possum CBD, SO and attached duodenum (n= 18) was mounted in an organ bath.

Conduction of hyperpolarization along hamster feed arteries: augmentation by acetylcholine.

The conduction of vasodilation along resistance vessels has been presumed to reflect the electrotonic spread of hyperpolarization from cell to cell along the vessel wall through gap junction channels. However, the vasomotor response to acetylcholine (ACh) encompasses greater distances than can be explained by passive decay. To investigate the underlying mechanism for this behavior, we tested the hypothesis that ACh augments the conduction of hyperpolarization.