The effects of autonomic drugs on closure of the internal urethral orifice during ejaculation were investigated in dogs.
Methods and materials. The closure of the internal urethral orifice was measured with latex balloon inserted into the orifice. Seminal emission and ejaculation were measured with posterior urethrogram. In this study the nerve fibers descending on the anterior wall of the aorta into the plexus were tentatively named as the central branch of the lower mesenteric. plexus and fibers entering from the lateral portion into the plexus as the lateral branch of the plexus. These two groups of the fibers were cut and the peripheral end of the cut fibers were electrically stimulated with square waves of 2 msec, 10Hz and 2V. To cause closure of the internal urethral orifice, the lateral branch was stimulated with above-mentioned condition for 3sec in every 20sec. And to cause seminal emission and ejaculation the central branch was stimulated continuously.
The autonomic drugs were given into the aorta just above its bifurcation.
The results obtained are as follows:
1) Effect of α-adrenergic drugs. Administration of phenylephrine (α-stimulant), 10-100μg, caused closure of the internal urethral orifice and phentolamine (α-blocker), 1-10mg, suppressed the closure. Seminal emission was suppressed completely by phentolamine, and rhythmic alterations of posterior urethral pressure, which is considered as ejaculation, were also abolished. With α-stimulant the rhythmic alterations were induced.
2) Effects of β-adrenergic drugs.
Isoproterenol (β-stimulant), 10-30μg, depressed the closure of the internal urethral orifice and propranolol (β-blocker), 1-10mg strengthened it. But these depressing and strengthening effects are thought to be pretencious phenomena.
Seminal emission and the rhythmic alterations of the posterior urethral pressure did not show any significant change after administration of the β-stimulant and β-blocker.
3) Effects of cholinergic and anticholinergic drugs.
Acetylcholine (1-10μg) and atropine (1-10μg) did not show any significant effect on closure of the internal urethral orifice as well as seminal emission and rhythmic alteration of the posterior urethral pressure.
4) Effects of ganglion stimulant and blocker.
Closure of the internal urethral orifice was strengthened by DMPP (10-30μg), and was suppressed by hexamethonium (100-500μg). No significant effect on seminal emission or the rhythmic alterations were observed.
From these results it is concluded that the internal urethral orifice during ejaculation as well as seminal emission and ejaculation is predominantly under the control of α-adrenergic receptor mechanism.

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The peripheral nervous controls of seminal emission and closure of the internal urethral orifice during ejaculation were examined experimentally and the hypothesis reported in the previous paper was confirmed.
Methods: The hypogastric nerve and the fibers entering the hypogastric plexus which were grouped and referred to as the central branch of the hypogastric plexus and the lateral branch were exposed and sectioned. After 1-4 weeks postoperatively, the penis of the operated dogs was manually stimulated without anesthesia and changes in ejaculation were observed.
The results obtained are as follows:
i) Section of the bilateral hypogastric nerves. Ejaculation did not occur after 1-4 weeks postoperatively. Disappearance of ejaculation was found to be due to retrograde ejaculation, i. e. regurgitation of the semen into the bladder, but not due to the loss of seminal emission.
ii) Selective section of the nerve fibers entering the hypogastric plexus.
In the dogs whose median branch was cut, ejaculation occurred just like before section of the branch. No retrograde ejaculation occurred in these dogs. In 5 dogs whose lateral branch was sectioned, ejaculation disappeared in all dogs. In 3 of the 5 dogs retrograde ejaculation occurred and in a dog many spermatozoa were found in the urethra. In only one dog emission disappeared completely.
From these results it is concluded that the nerve fibers controlling seminal emission and closure of the internal urethral orifice during ejaculation may take different passways above the hypogastric plexus and these results also confirmed those reported in the previous report.

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The effects of autonomic drugs on seminal emission and ejaculation were investigated in mongrel dogs. Changes in the posterior urethral pressure (Posterior Urethrogram) and the volume of seminal emission during continuous hypogastric nerve stimulation were measured in different dogs. The seminal emission induced by hypogastric nerve stimulation caused continuous rise in the posterior urethral pressure. When the pressure reached the maximum level, a rhythmic alteration of the pressure which was considered to be a phenomenon identical to ejaculation occurred. The drugs were administered into the aorta close to the bifurcation.
The following results were obtained: Tetrodotoxin (1-5μg) abolished both seminal emission and rhythmic alterations of the posterior urethral pressure. Phenylephrine (10-100μg) and methoxamine (10-30μg) markedly increased the seminal emission and induced the rhythmic alterations. Phentolamine (1-10mg) and phenoxybenzamine (1-10mg) abolished both seminal emission and the rhythmic alterations. Administration of isoproterenol (10-30μg) or propranolol (1-10mg) affected neither seminal emission nor the rhythmic alterations. Acetylcholine (1-10μg) or atropine (1-10μg) did not show any definite effect on both seminal emission and on the rhythmic alterations. No significant effect of DMPP (10-30μg) on seminal emission or on the rhythmic alterations was observed. No significant change in seminal emission was caused by hexamethonium (100-500μg). The rhythmic alterations were not affected by the agent in most dogs.
From these results it is concluded that both semiqal emission and ejaculation are predominantly under the influence of the adrenergic nervous system, particularly through an α-adrenergic receptor mechanism.

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The effects of Chromomycin A₃(CmA₃), Mitomycin C (M. M. C), and Nitromin on metastasis of AH 130 hepatoma implanted in the rat urinary bladder were studied by histologic examination.
The results obtained were as follows:
1) The rats which received on intraperitoneal administration of M. M. C 0.5mg/kg/day, were found to be free from metastasis, despite of tumor formation in the implanted site in the urinary bladder. The rats which received a combined administration of M. M. C 0.1mg/kg/day and Nitromin, 1mg/kg/day, into the abdominal cavity were also free from metastasis, except in the retroperitoneal lymph nodes.
2) By either single or combined intravenous administration of M. M. C, Nitromin, and CmA₃ hematogenous metastasis was prevented fairly well, but lymphogenous and continous metastases could not be satisfactorily prevented.
3) Intravenous administration of CmA₃ did not prevent metastasis to the retroperitoneal lymph nodes, lung, and spleen. The extensive metastasis in the spleen in the rats administrated with this drug was characteristic.
4) Generally speaking, each antitumor agent used in this study showed some preventive effects on the metastases except retroperitoneal lymph nodes. However, M. M. C showed a marked preventive effect on the metastasis in the retroperitoneal lymph nodes, when it was given intraperitoneally in a dosage of 0.5mg/kg/day.
From the above results it was considered that the antitumor agents had only a slight effect on the original, implanted tumor and on lymphogenous metastasis, and that these agents were more effective when they were combined with radical surgical operation.

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In this paper an attempt was made to elucidate the mechanism of the transportation of spermatozoa in the vas deferens in male mongrel dogs.
Methods: Intraluminal pressure of the vas deferens was measured in vivo by inserting one or two polyethylene tubes to the lumen of the vas deferens and the number of the spermatozoa transported to the end of the vas deferens or to the posterior urethra was measured. The autonomic drugs were administered intra-aortically.
Results are as follows:
1. Autonomic contraction of the vas deferens. Measurement of the intraluminal pressure clarified that the vas deferens repeated autonomic contraction. This contraction was not so-called peristalsis but the entire portion of the vas deferens contracted simultaneously. When autonomic contraction was repeating, the posterior urethra was washed with physiologic saline every 15 minutes. One or two spermatozoa were present in every 400x field of the sediment of the saline. Then, the lumen of the vas deferens was irrigated with 2.5% and 10% formalin for 10 minutes to inhibit the cilial movement of the epithelium and the movement of the spermatozoa. Even after the irrigation the spermatozoa were present in the posterior urethra. These results indicate that the spermatozoa in the cauda epididymidis and the proximal portion of the vas deferens are continously transported by the autonomic contraction and that transportation of spermatozoa is not confined to ejaculation.
2. Stimulation of the hypogastric nerve. Stimulation of the hypogastric nerves caused a rise of the pressure at the proximal portion of the vas deferens. The rise of the pressure began 5-10 seconds after the commencement of the stimulation. The pressure near the peripheral end of the vas deferens began to rise 5-10 seconds later than the rise of the pressure of the proximal portion. Then, the testis and epididymis was separated with a ligature between them. Hypogastric nerve stimulation caused a rise of the intra-luminal pressure of the vas deferens like before the ligation. After the ligature of the transitional portion between the epididymis and vas deferens the intraluminal pressure of the vas deferens rose by hypogastric nerve stimulation. The vas deferens was separated into two portions, i. e., the proximal and distal portions with another ligature at its mid-portion in addition to the ligature between the epididymis and vas deferens. The stimulation of the hypogastric nerves caused a rise in the pressure of the proximal portion, whereas a slight fall followed by a slight rise was observed in the pressure of the distal portion. Actually, hypogastric nerve stimulation transported a considerable number of spermatozoa to the peripheral end of the vas deferens. These results indicate that spermatozoa are transported in the following manner: During ejaculation the stimuli through the hypogastric nerves elevated the pressure in the ductus epididymidis and the proximal portion of the vas deferens. This elevation pressed the spermatozoa from the epididymis and proximal portion of the vas deferens toward the posterior urethra.
3. The effect of the autonomic drugs on the transportation of spermatozoa by hypogastric nerve stimulation. Phentolamine in a dose of 1-10mg suppressed the rise of the intraluminal pressure of the vas deferens induced by hypogastric nerve stimulation and blocked the transportation of the spermatozoa in the vas deferens. Almost no changes were observed in the rise of the intraluminal pressure of the vas deferens and in the transportation of the spermatozoa after the administration of propranolol (1-10mg), atropine (1-10μg) or hexamethonium (100-500μg). These results indicate that an α-adrenergic mechanism is mainly involved in the transport of spermatozoa in the vas deferens.
4. Effects of sectioning of the peripheral nerves and the administration of autonomic drugs on the autonomic contration of the vas deferens. Sectioning of the hypogastric ner

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