PURPOSE: PDE 4 inhibitor is known to be a bladder relaxant. In this study, the effects of PDE 4 inhibitor on the urinary bladder function were evaluated in vivo experiment. We postulated that PDE 4 inhibitor of appropriate concentration might be helpful in the treatment of overactive bladder. MATERIALS AND METHODS: Fifteen Spraque-dawley female rats, weighing approximately 250~300 mg, were used for this study and divided into three groups. PDE 4 inhibitor 486,051 was administrated to each rat by different drug concentrations(0.5 mg/kg, 1 mg/kg, 5 mg/kg). Cystometrogram(CMG) was performed before and 20~60 minutes afterV), bladder capacity(BC), maximal bladder voiding contraction pressure(MVP), intercontrac drug application considering first voiding. Cystometric parameters investigated were voided volume(VV), residual volume (RV), bladder capacity(BC), maximal bladder voiding contraction pressure(MVP), intercontraction interval(ICI). Mean blood pressure was monitored in all rats. RESULTS: PDE 4 inhibitor of 0.5 mg/kg increased the intercontraction interval but not the bladder capacity significantly. PDE 4 inhibitor of 5 mg/kg increased the bladder capacity significantly, but did not show the increased intercontraction interval compared to other groups, and showed the greatest increased residual volume among three groups. PDE 4 inhibitor of 1 mg/kg showed the most increased intercontraction interval and the bladder capacity, and the least decreased voided volume and maximal bladder voiding contraction pressure change. CONCLUSION: PDE 4 inhibitor of different concentrations affects cystometric parameters variably by bladder smooth muscle relaxant. PDE 4 inhibitor of appropriate concentration may be helpful in the treatment of overactive bladder. PDE 4 inhibitor, at the concentration of 1 mg/kg, increased the bladder capacity and intercontraction interval most significantly. This study may provide an important basic data in the future when drug effects were assessed in variable animal models of overactive bladder, etc. However, main limitations of drug use are the increase of residual urine and the decrease of blood pressure. Therefore more bladder specific drug is needed.
Animals ; Blood Pressure ; Female ; Humans ; Models, Animal ; Muscle, Smooth ; Rats* ; Residual Volume ; Urinary Bladder* ; Urinary Bladder, Overactive

BACKGROUND/AIMS: Colonoscopy training programs and the minimal experience with colonoscopy required to be considered technically competent are not well established. The aim of this study was to determine the colonoscopy learning curves and factors associated with this difficult procedure at a single center. METHODS: A total of 3,243 colonoscopies were performed by 12 first-year gastroenterology fellows, and various clinical factors were assessed prospectively for 22 months. Acquisition of competence (success rate) was evaluated based on two objective criteria: (i) the adjusted completion rate (>90%) and (ii) cecal intubation time (<20 minutes). RESULTS: The overall success rate in reaching the cecum in less than 20 minutes was 72.8%. The cecal intubation time was 9.34+/-4.13 minutes (mean+/-SD). Trainees' skill at performing cecal intubation in <20 minutes reached the requisite standard of competence after 200 procedures. Cecal intubation time decreased significantly from 11.3 to 9.4 minutes after 100 procedures and improved continuously thereafter. Female patients and advanced patient age (over 60 years) were associated with prolonged cecal intubation time (>20 minutes). Surgery of the uterus and ovaries was significantly correlated with delayed cecal intubation time, but not after sufficient colonoscopy experience. CONCLUSIONS: The minimum number of procedures to reach technical competence was 200. The cecal intubation time was longer in female and older patients.
Cecum ; Colonoscopy ; Female ; Gastroenterology ; Humans ; Intubation ; Learning ; Learning Curve ; Mental Competency ; Ovary ; Prospective Studies ; Uterus