High K-induced contractions in the smooth muscle of rabbit aorta and guinea pig taenia coli may be described as follows: High K depolarizes the smooth muscle cell membrane and opens voltage dependent Ca channels, resulting in an influx of extracel-lular Ca and an activation of contractile machinery. A part of the cellular Ca is taken up by mitochondria. Oxygen consumption of the muscle increases to compensate for the ATP consumed by contraction. Hyperosmotic high K solution induces osmotic shrinkage of the cell which uncouples membrane excitation from contraction. Isosmotic high K, Na deficient solution induces swelling of the cell and also inhibits the synport of Na and glucose resulting in an ATP deficiency; both of the changes could inhibit muscle contractile tension. Na deficiency may also stimulate Ca influx coupled to N a efflux in some smooth muscle preparations although such mechanism does not seem to play an important role in rabbit aorta and guinea pig taenia coli.

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New equipment based on field gradient principle for measurement of cross sec-tional area of ureteral urine bolus has been developped. Inside the probe consisted of a Fr. 4 ureteral catheter, there are 4 ring impedance electrodes and a bipolar ring ureteromyographic electrode.
Ex vivo experinents has proved high values in reliability and reproducebility of obtained cross sectional area of urine bolus through an impedance method.
Following results have been obtained through animal and clinical experiments.
1. As urine bolus passed through the impedance electrodes, impedance represent-ed the cross sectional area of urine bolus.,
2. The ureteral activity corresponded to the increase of urine flow changed as follows, (a) ureteral peristaltic frequency increased, (b) cross sectional area of urine bolus increased, (c) length of urine bolus increased, (d) during maximum diuresis, peristaltic activity diminished and continous flow presented through ureteral column.,
3. It will be useful method for experimental or clinical evaluation of ureteral function.

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For the purpose of evaluating the tissue blood flow reducing effect on loweresophagus and cardiac portion of the stomach after transabdominal mucosal transection operation for esophageal varices, 28 adult mongrel dogs were used and devided into (A) 18 as the control (B) 10 caused to have portal hypertention for present study.
Closed-couple thermoelectrode flow meter was used to measure the tissue blood flow at lower esophagus and carciac portion of the stomach following this procedures (1) ligating short gastric vessels, (2) ligating left gastric vessels, (3) transecting only the mucosal tube of the esophagus, (4) completely transecting of the esophagus.
The following results were obtained.
1. Effect on lower esophagus: transecting only the mucosal tube of the esophagus reduced 36.0±11.0% of the tissue blood flow and ligating short gastric vessels or left gastric vessels also reviewed a rather large effect.
2. Effect on cardiac portion of the stomach: ligating the short gastric vessels reduced 2.5±3.0% of the tissue blood flow, while ligating of the left gastric vessels reduced more effectively 13.6±6.5%.

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The dual autonomic innervation of the urinary bladder of the female rat was studied using histochemical and light and electron microscopic methods. The bladder body in the normal state had a rich supply of cholinergic nerve fibers with a uniformly reticular pattern, but it was sparsely supplied with adrenergic nerves mainly associated with the blood vessels rather than the detrusor muscles.
Seven days after the unilateral extirpation of the pelvic ganglion, most cholinergic and adrenergic fibers on the ipsilateral side of the bladder body disappeared markedly with the use of enzymatic and fluorescent histochemical techniques. The acetyl-cholinesterase activity of cholinergic fibers and the intensity of fluorescence of adrenergic fibers were somewhat restored 14 days after the operation. Seventy days postoperatively, it was found that the former had recovered in the relatively fine nerve fibers, while the latter had been almost completely restored, compared with the normal adrenergic innervation of the bladder body.

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The effects of prostaglandin (PG) F_2α and E₂ on the denervated smooth muscle of the urinary bladder in female rats were studied in vivo by histochemistry and electron microscopy. The urinary bladder denervated by bilateral removal of the pelvic ganglion was markedly distended, being filled with urine. Daily intravenous adminis-tration of PGF_2α or PGE₂ for 6 days following the operation showed that rats receiving PGE₂ urinated remarkably more than those receiving PGF_2α. But the ultrastructual changes on the smooth muscle cells, such as dilated tubules of rough endoplasmic reticulums and large Golgi vacuoles, were more prominent in the PGF_2α administrated urinary bladders than in PGE₂ anministrated ones.
On occasion, cholinergic ganglion cells happened to be encountered in the muscular layer of a rat urinary bladder. These intramural ganglion cells and the cholinergic nerve fibers surrounding the cells displayed strong acetylcholinesterase activity, unaffected by bilateral pelvic ganglionectomy.

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Manometric study was performed to compare the inhibitory effect of glucagon and secretin on the gastroduodenal motor activity by infused catheter method. The subjects consisted of 3 healthy volunteers and 7 patients with peptic ulcer and other diseases.
The following results were obtained.
1) After the intravenous administration of glucagon (1 mg), the motor activity of the stomach and duodenum was inhibited promptly. According to statistic evaluation, the contraction numbers and motility index decreased significantly during 25 minutes compared with the basal values in both stomach and duodenum.
2) After the administration of secretin (100 units), gastric motor activity was markedly inhibited, although duodenal motility increased during 10 minutes due to the initiation of secretin-induced migrating motor complex. The contraction numbers and motility index in stomach decreased significantly during 20 minutes after the administration.
3) The inhibitory effect of glucagon was more remarkable in duodenum than in stomach. On the other hand, secretin was more effective in stomach than in duodenum.

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