抄録
1. The isolated jejunal loop of guinea pig was perfused by means of modified TRENDELENBURG'S method to study the effect of the pressure-raising upon the velocity of propagation of contraction waves. Action potentials were intracellularly detected from the longitudinal muscle by means of the floating microelectrodes, which were situated at two points along the long axis of the loop and about 10mm apart from each other. The spikes were used as the criterion of the passage of contraction wave.
2. With increase of the intraluminal pressure the velocity of the propagation of contraction wave was increased. The rate of increase of the velocity was in many cases 1.5-2.2mm/sec/mmH2O so that the velocity could attain 60-80mm/sec at the intraluminal pressure as high as 40 mmH2O.
3. The propagation of contraction waves was accelerated on the application of acetylcholine as well as physostigmine, while it was retarded by atropine.
4. On the basis of the results obtained in the present and previous experiments the underlying mechanism of the phenomena may be presumed to be as follows: The rise of the pressure produces the intrinsic mucosal reflex as a result there occurs from the intramural nervous elements the release of acetylcholine, which is responsible for accelerating the transmission of excitation from cell to cell.
