The author developed a new electromyography of the detrusor muscle which is applicable also for clinical examinations and obtained the following results:
1. In the normal bladder no action potential appeared when the organ was not full yet.
2. When the intravesical pressure was raised by introducing saline into trie bladder, spikes appeared.
3. Spikes of high frequency appeared with the onset of voiding.
4. In the normal bladder no action potential appeared by administration of 5 to 7 mg mecholyl.
5. From some muscles of the dome of the bladder was obtained spontaneous spike potential consisting of spike burst of about 10 spikes. In an animal experiment using adult dogs the spikes of the simple type appeared. The discharge interval was about 5 seconds.
6. In the bladder with damaged peripheral nerve, spikes appeared during veridical quiescence.
7. In the bladder with damaged peripheral nerve, spikes of high frequency appeared by administration of 5 to 7 mg mecholyl.

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For the long term observation of the electrical activity of the canine alimentary tract, a bipolar silver electrode was devised in our laboratory.
The electrode has been demonstrated to be satisfactory in sensing the electrical activity of the alimenatry tract.
The electromygoram of the esophagus was consisted of very fast spike burst lasting for about 3 to 5 seconds in swallowing actions. The stomach showed a cyclically recurring basic electrical rhythm (BER), which was propagated caudally, and spike burst which was related to the contractile activity of the gastric smooth muscle.
The duodenum and small bawel also showed both BER and spike burst in their electrical activity. Thus the electromyograms obtained by our electrode have shown their similarity to those by monopolar electrodes. Furthermore, our electrode has proved its durability, functioning for more than 5 months.
Details of the construction of our electrode were described.

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The experiments were performed to study the effects of Flavoxate Hydrochloride on the gastrointestinal motility and its underlying mechanism.
Gastrointestinal motility was inhibited at first and then accelerated markedly after the intranveous injection of Flavoxate hydrochloride (10mg/kg) in the experiments of anesthetized dogs. For analyzing the underlying mechanism of this response the following experiments were executed.
1) The pendular movements of isolated ileum of rabbits were accelerated with administration of low concentration of Flavoxate hydrochloride less than 10^-5g/ml, while these were reduced with administration of high concentration more than 10^-4g/ml. Because the tetrodotoxin (2.5×10^-7 g/ml) has no essential effect on this responses, it could be postulated that Flavoxate Hydrochloride has direct effect on intestinal smooth muscle itself.
2) Flavoxate hydrochloride (10mg/kg) induced the differentiated regional response of the sympathetic outflow, that is the parallel decrease of cutaneous and cardiac sympathetic activities, and the converse increase of splanchnic activity. Therefore, Flavoxate hydrochloride is thought to have an effect on the integrating mechanism of the sympathetic nervous system. This view was also supported by the experiments with neuromuscular preparation of lobster (Panulirus japonicus).
It is concluded from these results, that the change of gastrointestinal motility induced by intravenous injection of Flavoxate hydrochloride (10 mg/kg) is influenced both by its effect on the gastrointestinal smooth muscle itself and by its effect via the autonomic nervous system.

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