The slow wave in the circular muscle of the guinea-pig stomach.

Abstract

The slow wave in the circular muscle of guinea-pig stomach was investigated with the double sucrose-gap method. 2. The amplitude of the slow wave was reduced by depolarization, and it was increased by a small hyperpolarization (5-10 mV). With hyperpolarization greater than 15 mV the amplitude decreased, and the slow wave became reduced, and less dependent on polarization. This residual was not abolished by strong hyperpolarizing current pulses. 3. The frequency of the slow waves was not much affected by membrane polarization. The change was only 15-20% by depolarization or hyperpolarization of 12mV. 4. Rythmic inward currents could be recorded under voltage-clamp conditions. The frequency of the inward currents was the same as that of the slow wave. The intensity of inward current was little affected by membrane polarization. 5. Lowering the temperature reduced the frequency of the slow wave. The rates of rise and fall of the component which remained during strong hyperpolarization were similarly decreased by lowering the temperature. The Q10 of the frequency was about 2-7. 6. It is suggested that the slow wave consists of two different components. One is generated by a potential independent process, and triggers the second component which is potential dependent. The first component may be controlled by some metabolic process.