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H Noto

Publications and source records attributed to H Noto.

At least 55 records · Page 3Linked to original sources
PubMed1991

Properties of the descending limb of the spinobulbospinal micturition reflex pathway in the cat.

The micturition reflex is thought to be mediated by a spinobulbospinal reflex pathway passing through the rostral pons. This study examined the properties of the descending limb of the reflex pathway by monitoring the responses of the lower urinary tract to stimulation of the pons in the decerebrate cat. Electrical stimulation (300 microseconds pulses at 50 Hz intratrain frequencies, 300-500 ms trains, 0.5-15 V) in the region of the locus coeruleus (P 0.5-3.1/L 2-4/H to -2.75) was used to activate the descending excitatory pathway to the sacral parasympathetic nucleus. Low intensity stimulation induced small amplitude, short duration (14 +/- 11 cm H2O, 10 +/- 3 s) bladder contractions in a partially full bladder, whereas higher intensity stimulation induced large amplitude, long duration (69 +/- 29 cm H2O, 70 +/- 44 s) contractions which were similar to distension-induced reflex micturition contractions. The evoked bladder contractions coincided with a reduction in external urethral sphincter (EUS) EMG activity. Following bilateral L7-S3 dorsal root transection, electrical stimulation of the pons still elicited the small amplitude bladder contractions, but the larger amplitude, long duration micturition contractions were abolished. During these small evoked bladder contractions, a suppression of EUS activity still occurred following deafferentation, indicating a pontine mediated bladder/EUS synergy. It is concluded that the pons can initiate bladder contractions and coordinated bladder-sphincter activity, but that afferent feedback (via the dorsal roots) is needed to maintain the large amplitude micturition contractions.

Animals↗
PubMed1991

Electrophysiological analysis of the ascending and descending components of the micturition reflex pathway in the rat.

Electrophysiological techniques were used to examine the organization of the spinobulbospinal micturition reflex pathway in the rat. Electrical stimulation of afferent axons in the pelvic nerve evoked a long latency (136 +/- 41 ms) response on bladder postganglionic nerves, whereas stimulation in the dorsal pontine tegmentum elicited shorter latency firing (72 +/- 25 ms) on these nerves. Transection of the pelvic nerve eliminated these responses. Firing on the bladder postganglionic nerves was evoked by stimulation in a relatively limited area of the pons within and close to the laterodorsal tegmental nucleus (LDT) and adjacent ventral periaqueductal gray. Stimulation at sites ventral to this excitatory area inhibited at latencies of 107 +/- 11 ms the asynchronous firing on the bladder postganglionic nerves elicited by bladder distension. Electrical stimulation of afferents in the pelvic nerve evoked short latency (13 +/- 3 ms) negative field potentials in the dorsal part of the periaqueductal gray as well as long latency (42 +/- 7 ms) field potentials in and adjacent to the LDT. The responses were not altered by neuromuscular blockade. Similar responses were elicited by stimulation of afferent axons in the bladder nerves. The sum of the latencies of the ascending and descending pathways between the LDT and the pelvic nerve (i.e. 72 ms plus 42 ms = 114 ms) is comparable although somewhat shorter (22 ms) than the latency of the entire micturition reflex. These results provide further evidence that the micturition reflex in the rat is mediated by a spinobulbospinal pathway which passes through the dorsal pontine tegmentum, and that neurons in the periaqueductal gray as well as the LDT may play as important role in the regulation of the micturition.

Afferent Pathways↗
PubMed1991

Opioid modulation of the micturition reflex at the level of the pontine micturition center.

In precollicular decerebrate cats and dogs the intravenous administration of naloxone reduced urinary bladder capacity. Successive cystometrograms revealed that naloxone in doses of 10-100 micrograms/kg i.v. reduced the volume necessary to evoke micturition by 21-67% (mean 48%) in cats and 15-81% (mean 43%) in dogs, respectively. Microinjection of fentanyl (0.4-10 nM) into the pontine micturition center (PMC) increased the bladder capacity by 4-46% (mean 18%) in cats. Naloxone injected into the same site reversed the effect of fentanyl. Microinjection of naloxone (40-120 nM) into the PMC reduced the bladder capacity by 17-57% (mean 34%) in cats. These data indicate that endogenous opioid peptides may have a role in controlling micturition in both decerebrate cat and dog, and that the enkephalinergic inhibitory mechanisms are important in modulating the micturition reflex at the level of the pontine micturition center.

Animals↗
PubMed1991

[Experimental and clinical studies of urethral anesthesia on etiology and treatment of detrusor-sphincter dyssynergia].

We studied whether detrusor-sphincter synergia during micturition was obtained by means of urethral anesthesia with lidocaine hydrochloride in five thoracic spinal cats and eight clinical cases with detrusor-sphincter dyssynergia. In thoracic spinal cats with detrusor-sphincter dyssynergia, urethral anesthesia produced detrusor-sphincter synergia, an increase in the maximum bladder pressure and a decrease in the residual volume. In clinical cases with detrusor-sphincter dyssynergia, urethral anesthesia produced detrusor-sphincter synergia or a decrease in the external urethral sphincter activities during micturition, and a decrease in the maximum urethral closure pressure and the residual volume. There were no remarkable changes of the external urethral sphincter activities during urine storage phase before and after urethral anesthesia in both spinal cats and clinical cases. These results suggest that urethral anesthesia blocks the urethro-urethral contraction reflex and secondarily activates vesico-urethral relaxation reflex. The block of urethral sensory nerves is thought to effectively treat detrusor-sphincter dyssynergia.

Anesthesia, Local↗
PubMed1991

[Identification of effective region of the pons in response to inaperisone which facilitates urine storage].

To identify the effective region of the pons in response to inaperisone which facilitates urine storage, inaperisone (100 mM, 0.2 microliters) was injected into the nucleus locus coeruleus alpha (LCa, the pontine micturition center), the nucleus locus subcoeruleus (LSC, the pontine urine storage center) and the nucleus reticularis pontis oralis (PoO, micturition inhibitory region) of the decerebrate cats. On reflex micturition, inaperisone injection into the LSC decreased voiding volume, and increased residual volume and bladder capacity, significantly. However, there was no difference in the maximum bladder pressure before and after inaperisone injection into the LSC. Inaperisone injection into the LCa or the PoO had no influence on reflex micturition. These results suggest that effective region of the pons in response to inaperisone is the LSC, and that inaperisone facilitates the urine storage neural mechanism in the LSC.

Animals↗
PubMed1991

[Non-invasive imaging diagnosis of left renal vein compression causing hematuria. Part 1. Ultrasonography].

Left renal veins of 100 out-patients were examined by transabdominal ultrasonography to evaluate its usefulness in determining left renal vein compression which is causing renal bleeding. Ultrasonography revealed the left renal vein in 86 patients. In 61 of the 86 cases, the internal cavity of left renal vein was opened at least in diastolic phase, but in 23 cases, the internal cavity was closed between the abdominal aorta and the superior mesenteric artery in both systolic and diastolic phases. In the remaining 2 cases, left renal vein was compressed at a point where it intersected the right renal artery. Left renal vein compression was observed in 18 (69%) of the 26 cases which had been classified as idiopathic renal bleeding and in 7 (26%) of the 27 cases which had urinary tract diseases causing hematuria. In 33 cases which did not have hematuria, left renal vein compression was not observed. These results suggest that diagnosis of left renal vein compression causing renal bleeding is possible by transabdominal ultrasonography.

Adolescent↗
PubMed1991

[Non-invasive imaging diagnosis of left renal vein compression causing hematuria. Part 2. CT].

Left renal veins of 77 patients were examined by computed tomography (CT) to evaluate its usefulness in determining the left renal vein compression which is causing renal bleeding. From CT image, left renal vein compression was observed in 6 (86%) of the 7 cases which had been classified as idiopathic renal bleeding, in 9 (21%) of the 42 cases which had urinary tract diseases causing hematuria, and in 3 (11%) of the 28 cases which did not have hematuria. In 15 of the 18 cases of left renal vein compression, left renal vein was compressed between the superior mesenteric artery and the abdominal aorta, showing so-called nutcracker phenomenon. In the remaining 3 cases, however, the superior mesenteric artery provided sharp delineation from the abdominal aorta. The superior mesenteric artery and the abdominal aorta made the mean angle of 35.5 degree in patients with normal left renal vein, the mean angle of 45.4 degrees in those with left renal vein compression without nutcracker phenomenon, and the mean angle of 11.9 degrees in those with nutcracker phenomenon. CT was superior to ultrasonography, in revealing left renal vein compression.

Adult↗
PubMed1990

Pontine control of the urinary bladder and external urethral sphincter in the rat.

Neurons in the rostral pontine tegmentum are known to have an important role in controlling micturition. The present experiments used urethane anesthetized rats to examine the effects of electrical stimulation at various sites in the pons on bladder and external urethral sphincter activity and on the volume threshold for inducing micturition. Stimulation with short trains of pulses (50 Hz, 1-3 s trains, 1-15 V) in the laterodorsal tegmental nucleus (LDT), the periaqueductal grey (PAG) or the lateral parabrachial nucleus (L-PBN) elicited contractions of a partially filled, quiescent bladder. However stimulation during a bladder contraction aborted the contraction indicating that these areas have inhibitory as well as excitatory effects. Continuous stimulation (50 Hz) in the PAG or L-PBN during a cystometrogram decreased bladder capacity (mean decrease 36%). Conversely, continuous stimulation in the pontine reticular formation (in or near the dorsal subcoeruleus nucleus and medial parabrachial nucleus) increased bladder capacity (mean increase 50%). Stimulation at pontine sites (LDT, PAG and L-PBN) which elicited bladder contractions also elicited an increase in external urethral sphincter activity. A similar increase in urethral sphincter activity occurred during reflex micturition induced by bladder distension. These data suggest that bladder capacity and the coordination of bladder and external urethral functions are controlled by various neuronal populations in the rostral pons of the rat.

Animals↗
PubMed1990

[A comparative study of the effects of propiverine, terodiline, oxybutynin on the lower urinary tract function in the decerebrate dog].

The effects of propiverine, terodiline, oxybutynin on the lower urinary tract function was studied by cystometry in 44 decerebrate dogs. Micturition was induced by bladder filling before and after the intravenous administration of each drug. The statistical analysis was carried out on the urodynamic parameters. Propiverine at a dose of 5, 10 mg/kg significantly increased the bladder volume. And, there was a substantial increase in the functional bladder volume at a dose of 10 mg/kg. Terodiline at a dose of 5 mg/kg also significantly increased the bladder volume and residual volume. Oxybutynin at a dose of 0.5 or 1 mg/kg produced a substantial increase in the bladder volume and residual volume, and produced a significant decrease in contraction pressure. Furthermore, there was a significant decrease in the functional bladder volume at a dose of 1 mg/kg. This study compared the three drugs under the same test conditions. Only propiverine increased the functional bladder volume, thus suggesting promise for the relief of pollakisuria in the clinical applications.

Animals↗
PubMed1989

Excitatory and inhibitory influences on bladder activity elicited by electrical stimulation in the pontine micturition center in the rat.

Electrical stimulation at various sites in the dorsal pontine tegmentum in urethane anesthetized rats modulated activity of the urinary bladder as well as efferent firing on bladder postganglionic nerves. Electrical stimulation (0.2 ms 50 Hz, 5-20 V or 30-150 microA, 2-5 s train duration) using a microelectrode (tip diameter, 10-20 microns) in an excitatory area located rostral and medial to the locus coeruleus evoked short latency (less than 2 s) large amplitude (greater than 20 cm H2O) bladder contractions and increased firing on the bladder postganglionic nerves. Stimulation at sites adjacent to the excitatory area inhibited bladder postganglionic nerve firing and bladder activity. Inhibitory responses were evident as either a decrease in intravesical pressure, an increased interval between bladder contractions, or an interruption or elimination of bladder contractions. The threshold intensity for excitation using a large electrode (2-4 V) was slightly higher than that for inhibition (1.5-2 V). The optimum sites for evoking bladder contractions were located in and close to the laterodorsal tegmental nucleus (LDT) and in the periaqueductal gray just dorsal or dorsolateral to the LDT. The extent of the area that induced bladder contractions was 0.5-1.2 mm in diameter in each rat when a microelectrode was employed for electrical stimulation. Electrical stimulation in the optimum site for evoking bladder contractions induced relatively little striated muscle activity and produced no short-latency blood pressure changes. The longer latency blood pressure changes associated with a spontaneous bladder contraction were still present following a stimulation of the dorsolateral pons. These data are consistent with the view that neurons in the dorsal pontine tegmentum play an important role in the regulation of urine storage as well as urine release.

Action Potentials↗
PubMed1989

Effect of cerebellectomy on reflex micturition in the decerebrate dog as determined by urodynamic evaluation.

The effect of cerebellectomy on reflex micturition in the decerebrate dog was investigated by cystometric and striated urethral sphincter EMG studies. Before and after cerebellectomy, reflex micturition consisting of bladder contraction and spasmodic contraction of the striated urethral sphincter occurred when a critical degree of filling was reached. Cerebellectomy showed no influence on the striated urethral sphincter EMG activity. However, cerebellectomy produced a significant decrease in threshold volume and threshold pressure during the collecting phase, and also in the contraction pressure and voided volume of the emptying phase. The present study suggests that the cerebellum plays an inhibitory role in the collecting phase and a facilitatory role in the emptying phase during the entire reflex micturition cycle of the decerebrate dog. Further study will have to be done concerning the neurotransmission mechanism that causes these different effects in the collecting and emptying phases.

Animals↗
PubMed1988

Pontine micturition center in the dog.

The function and location of the pontine micturition center was studied in ten decerebrate dogs by physiological experiments in which micturition induced by electrical stimulation of the pontine micturition center was compared with reflex micturition in response to bladder filling with physiological saline and by histological studies of the electrolytic lesions made at the stimulated areas. The micturition induced by electrical stimulation of the pontine micturition center showed the same pattern of detrusor contraction, simultaneous urethral relaxation and the elevation of the tail as reflex micturition in response to bladder filling. The peak contraction pressures in both micturitions showed no obvious differences. The electrolytic lesions were histologically identified at the locus coeruleus alpha in six out of 10 dogs, at the locus coeruleus in three and at the peri locus coeruleus alpha in one dog. The coordinated activities of bladder and urethra in the micturition induced by electrical stimulation of locus coeruleus or its subparts suggest that these areas perform an important role in the urine emptying function.

Animals↗
PubMed1987

Role of the pelvic nerve in the dynamics of micturition in the decerebrate dog as determined by suprapubic endoscopical and urodynamic evaluation.

The role of the pelvic nerves on the dynamics of micturition was evaluated in 13 decerebrate dogs, four male and nine female, by direct observation of bladder movement, by suprapubic cystoscopic observation of urethral behavior, and by pressure flow EMG studies. Experiments were performed before and after unilateral pelvic nerve transection. In control conditions and after unilateral pelvic nerve transection, the bladder neck was not tightly closed during the collecting phase, the membranous portion of the urethra opened and closed spasmodically during the emptying phase, and reflex micturition developed. Direct observation showed that after unilateral pelvic nerve transection, the ipsilateral bladder did not contract. A pressure flow EMG study showed that unilateral pelvic nerve transection produced a significant increase in threshold volume, threshold pressure, bladder compliance and residual volume, and a significant decrease in contraction pressure and flow rate. The present study shows that unilateral pelvic nerve transection has no demonstrable effect on urethral function, but has effects on bladder function during the collecting and emptying phases and that bladder innervation is unilateral in the dog.

Animals↗
PubMed1987

Transcystoscopic intracavitary irradiation for carcinoma of the bladder: technique and preliminary clinical results.

A remote controlled transcystoscopic intracavitary after-loading unit is introduced for irradiation therapy of bladder carcinoma. With intense radiation therapy a significant dose can be delivered to the tumor during a short interval. We treated 12 patients with transitional cell carcinoma of the bladder using transcystoscopic intracavitary irradiation. Of the patients 9 initially had a complete response, although within several months 3 subsequently had recurrence in a different part of the bladder. Technical difficulties and severe complications were not encountered. The preliminary results and technique of transcystoscopic intracavitary irradiation are reported.

Aged↗
PubMed1987

Primary mucin-producing adenosquamous carcinoma of the thyroid gland.

A rare case of mucin-producing adenosquamous carcinoma of the thyroid gland is reported in a 57-year-old woman. Light microscopically, much of the tumor showed a feature of mucin-producing adenosquamous carcinoma; squamous cells and mucous signet ring cells. In the lower portion of the tumor, a calcified area containing small foci of follicular carcinoma and its squamous cell metaplasia was accompanied. Histochemically, neutral, non-sulphated and sulphated acid mucins were found in the mucous cells, and no thyroglobulin or calcitonin was detected in the tumor cells. Electron microscopically, some tonofibrils and mucin production were observed concomitantly in the tumor cells. These findings suggested the possibility that this mucin-producing adenosquamous carcinoma originated from squamous cell metaplasia of pre-existing follicular carcinoma.

Adenocarcinoma, Mucinous↗