抄録
1. Applying the electrical stimulation on the isolated neurohypophysis of the rat, the oxytocin release was bioassayed and the compound action potential was recorded.
2. The repetitive pulse stimulation at the optimal frequency (about 20 Hz) was more effective on the oxytocin release than the excess K+ stimulation to the gland.
3. Two waves were separated in the compound action potential traveling along the stalk evoked by a single shock. The conduction velocity of the first wave was 1.64±0.26m/sec and that of the second wave was 0.69±0.17m/sec.
4. While a marked decrease in the size of the action potential was observed, the output of oxytocin was not declined by the repetitive stimulation at 10Hz or 20Hz.
5. The relation between the electrical activity and the secretory mechanism was discussed, and it is suggested that the depolarization at the nerve terminal may be directly linked to the secretory activity.
