Matsuki, Y. Dynamic stiffness of the isolated guinea-pig gall-bladder during contraction induced by cholecystokinin. Jap.J. Smooth Muscle Res., 1985, 21 (6), 427-438.-The visco-elastic properties of the isolated guinea-pig gall-bladder were investigated by the dynamic method. The sinusoidal volume changes (up to 0.2 ml) and the resulting sinusoidal pressure changes were displayed on the cathode ray oscilloscope, the volume being on abscissa and the pressure on ordinate.
The frequencies of the sinusoidal change in volume were 0.17-0.5 Hz which were 10 times higher than those in Schoetz et al.'s work (Am. J. Physiol. 241: G376-G381, 1981).
The dynamic pressure-volume relation of the resting gall-bladder was nearly linear, but showed the elliptical hysteresis loop during CCK-or ACh-induced contractions.
If frequencies of the. sinusoidal change in volume were increased to 1.7-3.3 Hz, the hysteresis loop for either relaxing or contracting gall-bladder became narrow and guiter-shaped. The dynamic stiffness, the slope of the hysteresis loop or the ratio of the maximum of pressure change to the maximum of volume change, increased in linear proportion to intraluminal pressure rise during contraction.
The data could be analysed on the assumption that the visco-elastic property of the gall-bladder was explained by two Voigt models placed in series. The one indicated the property of the smooth muscle tissue, and it had low elastance at the resting state, or middle-grade elastance together with high viscous resistance at the contraction state. Another one had high elastance and low viscous resistance, and it was characterized by collagen fibers involved within the organ.

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The short-lasting ‘burst’ activity was recorded from decerebrate, unanesthetized cats and dogs, by means of a single, bipolar needle electrode, originally aimed at recording of ‘slow spikes’ of internal anal sphincters. The recording of the ‘burst’ was more accessible in cats than in dogs, although the same macro-electrode, of which diameter was 0.3 mm, has been used throughout. There was no such species difference of accessibility for recording of ‘slow spikes’ of internal sphincters. Histological examinations indicated that the difference of accessibility may be due to relative thinness of muscular tissue in the cat.
Some of the bursts were seen simultaneously on the background of continuous ‘slow spikes’, however, the most of the bursts appeared in reciprocal manner with those ‘slow spikes’, namely, the bursts were elicited by rectal distension, while the ‘slow spikes’ of internal sphincters were wholly inhibited by the same distension. The participation of bursts to the anal canal pressure was little in fact, though the longitudinal length of anal canal was invariably shortened, whenever the repetitive bursts occured either spontaneously or in response.
It is concluded that the ‘burst’ activity is generated by longitudinal muscles of anal sphincters. The observation suggests further that cell-to-cell electrical communication does not operate between longitudinal and circular muscles in this portion, instead, that neural mechanism regulates dominantly for co-ordination of those muscles encircling the anal canal.

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Harada, T., Noto, H., Etori, K., Kumasaki, T., Kigure, T., Nishizawa, 0. and Tsuchida, S. The estimation of urine bolus volume for patients with congenital hydronephrosis. Jap.J. Smooth Muscle Res., 1985, 21 (6), 455-466. A new examination (bolusmetry) to evaluate the urine transport function of the ureteropelvic system was performed in 7 adult patients with congenital unilateral hydronephrosis. Whistle-tipped Fr. 5 catheters were introduced to each ureter about 5 cm proxymal from the ureteral orifice by transurethral endoscopic technique. Bolus volume and frequency, and changes in them caused by furosemide injection, were estimated by using a drop counter which was connected to the terminal end of the ureteral catheter.
Bolusmetry was performed comparing the hydronephrotic side and the healthy side, pre and postoperatively, and these results were then compared with a conventionalexamination.
We obtained the following results:
1) Bolus volume of the hydronephrotic side was 0.05±0.02 (mean±S.D.) ml at oliguric state, and it was significantly lower than the value of the healthy side which was 0.19±0.07 ml. Injection of diuretics increased the bolus volume of the healthy side ten times or more. On the other hand, the bolus volume of the hydronephrotic side was increased only slightly by the jnjection of furosemide, it being approximately one-fouth of the value of the healthy side.
2) The value of bolus frequency was similar to peristaltic frequency which was measured by the electromyogram. The tendency of a decrease was noticed in bolus frequency of the hydronephrotic side but it was not significant.
3) Of patients with severe hydronephrosis, the bolus volume of the hydronephrotic side was decreased and the response to the diuretics was not so significant. By bolusmetry, functional or organic obstruction of the ureteropelvic junction was detected.
4) Of 3 patients who had nephrectomy or nephrostomy, the kidney function had deteriorated severely. The bolus volume was lower than 0.25 ml at the diuretic state.
5) Bolus volume was increased postoperatively in 3 of 4 patients who had received pelvioplasty. One patient did not show the formation of bolus by the injection ofdiuretics, and the cause of the hydronephrosis was functional obstruction of the pelvioureteric junction.
We concluded that bolusmetry is a valuble method for evaluation of the function ofurine transport in the ureteropelvic system. Especially in hydronephrosis, bolusmetry is a useful in the choice of operative procedure, and for postoperative evaluation.

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Harada, T., Etori, K., Kumasaki, T., Kigure, T., Nishizawa, O. and Tsuchida, S. Evaluation of the pelvioureteral function through a new urine bolusmetry: Simultaneous measurement of urine bolus volume and electroureterogarm. Jap.J. Smooth Muscle Res., 1985, 21 (6), 467-480. -New equipment to evaluate the urine transport function of the ureteropelvic system has been developed . Simultaneous measuremtnt of urine bolus volume and electrical activity in the ureter is possible by means of this equipment. A urine bolus volume measuring system, which is based on the heat electrical method, is located in the probe tip, and bipolar electrodes for EMG are located in the stem of the Fr. 4 ureteral catheter.
Two kinds of experiments were performed. One was an examination of the new probe through a pervioureteric model using an infusion pump and Nelatons' catheters of various diameters. The other was an animal experiment. The changes in ureteral peristalsis and urine bolus volume in response to diuretics were examined in mongrel dogs through application of this equipment.
The following results were obtained:
1) There was a logarithmic relation between perfusion flow rate in catheters used as ureteral models and the values of voltage depression measured by the heat electrical method.
2) The urine bolus volume was calculated closely through a formula which had been developed from the model experiments.
3) In animal experiments, the bolus volume increased significantly and a tran sient increase in peristalsis was noted after the administration of diuretics although there was no significant change in peristaltic velocity.
4) Some pelvioureteric function parameters, i. e. peristaltic frequency, peristaltic velocity, urine bolus volume, bolume, bolus length and ureteral width, are feasible caluculations.
These results indicate that bolusmetry by using this new probe is a valuable method for evaluation of urine transport function in the pelvioureteric system, and suitable for clinical use as well as animal experiments.

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Proglumide suppressed neither phase III activity nor propagation of interdigestive migrating contractions (IMC) in the gastrointestinal tract.
Furthermore, proglumide did not inhibit the gastric motor activity stimulated by pentagastrin, however, it suppressed the pH in Pavlov pouch stimulated by pentagastrin in the interdigestive state.
On the contrary, in the digestive state, proglumide did not suppress the pH. That might be due to not only various gut hormones including gastrin, but also neural stimulation, mechanical stimulation and so on.
In conclusion, antigastrin effect of proglumide is rather remarkable on the acid secretion not on the gastrointestinal motor activity. Proglmide may be an antacid without suppression of motor activity.

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Cholecystokinin-octapeptide (CCK-OP) evoked contracion and ³H-acetylcholine (³H-ACh) release of the muscle strip of the guinea pig gallbladder were studied. Although hexamethonium (10^-5M) or tetrodotoxin (10^-6M) had no effect on CCK-OP (10^-8M) evoked contraction and ³H-ACh release, Ca-free medium almost completely abolished CCK-OP (10^-8M) evoked ³H-ACh release. In Ca-free medium contraction evoked by CCK-OP (10^-8M) was reduced to about 84%, which fitted well with the calculated reduction observed in the presence of atropine (10^-6M).
Dibutyryl cyclic GMP (10^-3M), which significantly reduced CCK-OP (10^-8M) evoked contraction to about 40%, had no effect on CCK-OP (10^-8M) evoked ³H-ACh release. CCK-OP receptors on the intramural cholinergic neurons might be suggested to be different from those on the muscle cells of the guinea pig gallbladder.

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