Previous studies have suggested that brain stem noradrenergic inputs differentially modulate neurons in the paraventricular nucleus (PVN). Here, we compared the effects of norepinephrine (NE) on spontaneous GABAergic inhibitory postsynaptic currents (sIPSCs) in identified PVN neurons using slice patch technique. In 17 of 18 type I neurons, NE (30-100microM) reversibly decreased sIPSC frequency to 41+/-7% of the baseline value (4.4+/-0.8 Hz, p<0.001). This effect was blocked by yohimbine (2-20microM), an alpha2-adrenoceptor antagonist and mimicked by clonidine (50 microM), an alpha2-adrenoceptor agonist. In contrast, NE increased sIPSC frequency to 248+/-32% of the control (3.06+/-0.37 Hz, p<0.001) in 31 of 54 type II neurons, but decreased the frequency to 41+/-7% of the control (5.5+/-1.3 Hz) in the rest of type II neurons (p<0.001). In both types of PVN neurons, NE did not affect the mean amplitude and decay time constant of sIPSCs. In addition, membrane input resistance and amplitude of sIPSC of type I neurons were larger than those of type II neurons tested (1209 vs. 736 M omega, p<0.001; 110 vs. 81 pS, p<0.001). The results suggest that noradrenergic modulation of inhibitory synaptic transmission in the PVN decreases the neuronal excitability in most type I neurons via alpha2-adrenoceptor, however, either increases in about 60% or decreases in 40% of type II neurons.
Brain Stem ; Clonidine ; Inhibitory Postsynaptic Potentials* ; Membranes ; Neurons ; Norepinephrine ; Paraventricular Hypothalamic Nucleus* ; Synaptic Transmission ; Yohimbine

PURPOSE: Overactive bladder is especially common in the elderly, although it is not regarded as a normal part of aging. Thus, we investigated how aging alters the cystometric and detrusor overactivity (DO) parameters and the density of nerve growth factor (NGF) in awake spontaneous hypertensive rats (SHRs) of different ages. METHODS: Three age groups of 12- (n=5), 17- (n=6), and 21- (n=6) week-old SHRs (Oriental Bio Inc.) were used. A catheter was implanted into the bladder to record the intravesical pressure (IVP), and a balloon-fitted catheter was positioned in the abdominal cavity to record the intraabdominal pressure (IAP). Of the IVP elevations above 2 cm H2O, DO was defined as a rise in IVP without a simultaneous change in IAP and was counted during the filling phase. We measured the expression of NGF in the bladders by enzyme-linked immunosorbent assay. RESULTS: Both the body and bladder weights significantly increased with age, but the normalized ratio between those was not changed. As for DO, none of the12-week-old rats showed DO, whereas the other groups did. DO increased significantly with age (P=0.0045 by Mantel-Haenszel trend test), although no significant differences were found in DO frequency or pressure between the 17- and 21-week-old age groups. NGF did not show any significant differences among the three groups. CONCLUSIONS: Our results showed that SHRs begin to shows DO after a certain age, such as 12 weeks of age, and that the occurrence of DO has a close relationship with aging. However, NGF, which is known to be increased in the bladder wall of patients with overactive bladder, did not show any relationship with aging in this study.
Abdominal Cavity ; Aged ; Aging ; Animals ; Catheters ; Humans ; Nerve Growth Factor ; Rats ; Rats, Inbred SHR ; Urinary Bladder ; Urinary Bladder, Overactive ; Urodynamics ; Weights and Measures

PURPOSE: The urodynamic effects of intravesical PGE2 instillation on bladder function and detrusor overactivity (DO) during the filling phase were investigated in rats by measuring intraabdominal and intravesical pressures simultaneously. MATERIALS AND METHODS: Continuous cystometry was performed inconscious, female and male Sprague- Dawley rats. We investigated pressure-, volume-, and DO-related parameters. RESULTS: Intravesical instillation of PGE2 increased all pressure-related parameters and decreased volume-related ones, compared to the control cystometric ones. However, among the total number of intravesical pressure rises (IVPRs) above 2 cmH2O during the filling phase, only 33% in female rats and 38% in male rats after PGE2 instillation were identified as true DO during the filling phase. CONCLUSIONS: Our findings suggest that the rat model with intravesical PGE2 is inappropriate for observing the effects of some drugs or mechanisms on DO, because only approximately 30% of IVPRs were confirmed as true DO. However, this model of intravesical PGE2 instillation has some advantages for the observation of changes in pressure and volume parameters rather than in DO-related ones.
Administration, Intravesical ; Animals ; Dinoprostone ; Female ; Humans ; Male ; Models, Theoretical ; Rats ; Urinary Bladder ; Urodynamics

PURPOSE: We investigated bladder function, with a special focus on nonvoiding contractions (NVCs), in awake rats with chronic chemical cystitis and bladder outlet obstruction (BOO) by use of simultaneous registrations of intravesical and intraabdominal pressures. In addition, we tested the effects of tolterodine on the NVCs in these models. METHODS: A total of 20 female Sprague-Dawley rats were used in this study. In eight rats, chemical cystitis was induced by intravesical instillation of HCl. Twelve rats were subjected to sham instillations or partial BOO. Four weeks after intravesical instillation or 2 weeks after partial BOO, cystometrograms were obtained by use of simultaneous recording of intravesical and intraabdominal pressure in all unanesthetized, unrestrained rats in metabolic cages. RESULTS: A total of 17 rats survived. In the rats with acute injury by HCl, 50% showed detrusor overactivity (DO), which was not seen in the sham group. The cystitis group had lower DO pressure without a difference in DO frequency compared with the BOO group. After the administration of tolterodine, the cystitis group showed no difference in DO frequency or pressure, whereas the BOO group showed decreased values for both parameters. CONCLUSIONS: Our study showed that toleterodine produced no effect on DO during the filling phase in rats with chronic chemical cystitisbut decreased the frequency and pressure of DO in rats with BOO. Clinically, studies are needed to improve the treatment effect of anticholinergic drugs ininterstitial cystitis patients with overactive bladder.
Administration, Intravesical ; Animals ; Benzhydryl Compounds ; Contracts ; Cresols ; Cystitis ; Female ; Humans ; Phenylpropanolamine ; Rats ; Rats, Sprague-Dawley ; Salicylamides ; Tolterodine Tartrate ; Urinary Bladder ; Urinary Bladder Neck Obstruction ; Urinary Bladder, Overactive ; Urodynamics

OBJECTIVEAccuracy of diagnostic methods for detecting Helicobacter pylori (H. pylori) infection among patients with bleeding peptic ulcers has not been thoroughly investigated. The aim of this study was to compare the diagnostic tests and their combined usage in detection of H. pylori infection in patients with bleeding gastric ulcers and without the use of nonsteroidal anti-inflammatory drugs.

METHODSA total of 57 patients who presented with bleeding gastric ulcers by endoscopy were enrolled. The status of H. pylori was identified by performing the rapid urease test (RUT), histology and (13)C-labeled urea breath test (UBT). The criteria for having H. pylori infection was a minimum of two positive tests.

RESULTSThe prevalence of H. pylori infection in our patient group was 80.7%. Among the three tests used: RUT, histology, and UBT, sensitivities were 56.5%, 97.8% and 100%, while specificities were 100%, 45.5% and 81.8%, respectively. The overall accuracies of the tests were 78.3%, 71.6% and 90.9%, respectively. Although UBT obtained significantly higher accuracy than histology (P = 0.02) as opposed to RUT (P = 0.11), UBT had significantly higher sensitivity than RUT (P < 0.001). In terms of combining any two of the three tests, more accuracy (98.9%) was achieved when both UBT and histology were used to confirm the diagnosis of the other. Conversely, failure to use combined tests generated the potential of missing a proper H. pylori diagnosis.

CONCLUSIONSUBT is superior to the other two tests in bleeding gastric ulcers. RUT lacks sensitivity for detection of H. pylori infection. However, the concomitant use of UBT and histology seems to be more accurate when gastric ulcers present with bleeding.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Breath Tests ; Female ; Helicobacter Infections ; diagnosis ; pathology ; Helicobacter pylori ; Humans ; Male ; Middle Aged ; Peptic Ulcer Hemorrhage ; complications ; Sensitivity and Specificity ; Stomach Ulcer ; complications ; Urea

PURPOSE: The aim of this study was to apply a new surgical procedure that allows for the successful monitoring of intraurethral pressure (IUP) changes in the cystometry of awake Sprague-Dawley rats. METHODS: Twenty-six female Sprague-Dawley rats were grouped according to the catheterization method (bladder only; bladder and urethra; or bladder, urethra, and abdomen). Using an arbitrarily determined initial point of the first phase among four rat micturition phases on the simultaneous curves as a reference point, we compared the time differences to the points on an intravesical pressure (IVP) and those on IUP or a detrusor pressure (DP) curve from intra-abdominal pressure (IAP). RESULTS: In awake rat, the start of urethral flow on IUP curve corresponded to the initial point of the second phase, which is same to the results on the anesthetized rat. However, certain results, such as micturition pressure (MP) and intraluminal pressure high-frequency oscillations (IPHFOs), differed between awake and anesthetized rats. Most MP values were checked after the end of urethral flow on the IUP curve, which is due to the peculiar methodology such as transvesical catheterization. Urethral flow was not completely interrupted during the IPHFOs, which suggests the presence of urethral wall tension against the flow during voiding. After removal of the superimposed effects of IAP from IVP, the DP curve clearly showed a peculiar shape, highlighting the possibility of using IAP in place of IUP to detect the flow starting point on the IVP curve. CONCLUSIONS: Awake rat cystometry results have been interpreted based on those in anesthetized rats. However, our awake cystometry data were substantially different in terms of voiding time compared to those of anesthetized rats. This discovery warrants careful interpretation of the voiding parameters in awake rat cystometry.
Animals ; Catheterization ; Catheters ; Female ; Humans ; Rats* ; Rats, Sprague-Dawley ; Urethra ; Urinary Bladder ; Urination ; Urodynamics

PURPOSE: The aim of this study was to investigate the effect of urinary bladder inflammation on bladder function in a rat chemical cystitis model. We also histologically confirmed the effects of inflammation in the detrusor on chronically inflamed bladder in rats. MATERIALS AND METHODS: A total of 13 female Sprague-Dawley rats were used in this study. In seven rats, intravesical instillation of HCl induced chemical cystitis, and the other rats with intravesical instillation of saline were used as the sham. After 2 weeks, cystometrograms were obtained with additional intraabdominal pressure measurements in all unanesthetized, unrestrained rats in metabolic cages. The rats were killed just after cystometry. The bladders were removed and examined histologically for mast cells and inflammatory changes. RESULTS: The rats with acute injury by HCl showed no differences in pressure parameters, including basal pressure, threshold pressure, and maximum bladder pressure, compared with the sham rats. They showed significantly increased bladder capacity, micturition volume, residual volume, and micturition interval compared with the sham group. They also showed an increased frequency of detrusor overactivity compared with the sham group. The percent of detrusor overactivity was 56.3% among the total intravesical pressure rises above 2 cmH2O. The histological findings of the rats with acute injury by HCl were consistent with chemical cystitis. CONCLUSIONS: Overlapping patterns of lower urinary tract symptoms and pelvic pain are common disease characteristics among interstitial cystitis patients. The situation in an animal model of interstitial cystitis is similar, as observed in this study by the histologic and awake cystometric examinations. However, the interstitial cystitis model showed detrusor overactivity during the filling phase without a decrease in bladder capacity and micturition intervals, which differs from the characteristics of overactive bladder patients.
Administration, Intravesical ; Animals ; Cystitis ; Cystitis, Interstitial ; Female ; Humans ; Inflammation ; Lower Urinary Tract Symptoms ; Mast Cells ; Models, Animal ; Pelvic Pain ; Rats ; Rats, Sprague-Dawley ; Residual Volume ; Salicylamides ; Urinary Bladder ; Urinary Bladder, Overactive ; Urination ; Urodynamics

PURPOSE: We investigated bladder function, with special focus on initial functional changes, by objective report of decompensated bladder according to the percentage of residual urine volume to bladder capacity in awake, obstructed rats. MATERIALS AND METHODS: Thirty rats were randomly subjected to sham operations (n=10) or partial bladder outlet obstruction (BOO, n=20). Cystometric investigations were performed without anesthesia 1 or 2 weeks after BOO surgery. To reduce the influence of confounding factors in awake cystometry, we used simultaneous recordings of intravesical and intraabdominal pressures. Decompensated bladder was defined as the bladder with more than 20% of residual volume compared with bladder capacity. RESULTS: Compared with that in sham animals, basal pressure was elevated in both BOO groups. Threshold pressure was higher in the 2 week BOO (p<0.01) group. Compliance was decreased in the 1 week BOO group (p<0.01) and increased in the 2 week BOO group (p<0.001). Bladder capacity was not increased in the 1 week BOO group, but was increased in the 2 week BOO group (p<0.01). Decompensation was found in 62.5% of the 1 week BOO group and in 33.3% of the 2 week BOO group. CONCLUSIONS: From the earlier phase, the bladders exhibited serial changes in pressure and volume parameters, and decompensated bladders defined by the percentage of residual volume to bladder capacity could be seen. During the later phase, there was an increasing tendency of compensated bladders, accompanied by the bladders being enlarged and more compliant.
Anesthesia ; Animals ; Compliance ; Rats ; Residual Volume ; Salicylamides ; Urinary Bladder ; Urinary Bladder Neck Obstruction ; Urinary Bladder, Overactive ; Urodynamics

PURPOSE: To compare the physical characteristics of detrusor overactivity (DO) induced by intravesical infusion of saline in awake, sham rats and rats with chronic spinal cord injury (SCI), by simultaneous registrations of intravesical and intraabdominal pressures. METHODS: Male Sprague-Dawley rats, normal or with a spinal vascular clip at the level of Th9, were investigated cystometrically 1 and 4 weeks after SCI. Intra-vesical pressure (IVP) and intra-abdominal pressure (IAP) were recorded simultaneously to evaluate true DO. During the filling phase, the event of IVP rises, defined as increments that exceeded 2 cmH2O from baseline, were determined as DO according to the absence of simultaneous changes in IAP. RESULTS: All SCI rats exhibited DO during the filling phase, which was not shown in sham rats. The frequency and pressure of DO had a tendency to decrease with time. The DO frequency of SCI rats after 4 weeks (0.9+/-0.2 min(-1)) was decreased compared with that after 1 week (2.1+/-0.4 min(-1); P<0.05). The DO pressure of SCI rats after 4 weeks (8.4+/-1.9 cmH2O) was decreased compared with that after 1 week (11.6+/-2.9 cmH2O; P>0.05). CONCLUSIONS: Cystometric studies in awake male SCI rats showed some significant changes in bladder function after SCI. All SCI rats exhibited DO during the filling phase, and showed different physical characteristics of DO over the course of time. The neurological basis of these time-related changes remains poorly understood, but may provide important prognostic information about long-term urological management in SCI patients.
Animals ; Humans ; Male ; Rats ; Rats, Sprague-Dawley ; Salicylamides ; Spinal Cord ; Spinal Cord Injuries ; Urinary Bladder ; Urinary Bladder, Overactive ; Urodynamics

No abstract available.