抄録
The salivary expulsion reflex in the human parotid was studied upon gustatory stimulation with 5% citric acid.
The volume of released saliva was measured with a device employing a pressure transducer and was demonstrated as an expulsion curve. Simultaneously, the output of the transducer was electrically processed by a “sample and hold” circuit and displayed on an ink recorder as a graph indicating expulsion velocity. With this method, it was possible to obtain measurement of a small volume of saliva which had been transiently expelled from the parotid duct in a short period of real time (below 0.1 sec). In the expulsion curve, small fluctuations were observed which were the result of small amounts of saliva expelled transiently from a parotid duct. Volume of outflow due to the transient expulsion varied but the time process of them was identical. Small amounts of continuous steady saliva were observed, although transient expulsions usually indicated intermittent patterns which had started during a regular period. We were then able to consider that the shape of the expulsion curve depended on the frequency and the amplitude of each transient expulsion. We suggested that because of several factors, the origins of the transient expulsion and intermittent expulsion pattern are related to the myoepithelial activity of the parotid gland.
