Urodynamic Findings in an Awake Chemical Cystitis Rat Model Observed by Simultaneous Registrations of Intravesical and Intraabdominal Pressures

Abstract

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 cmH 2 O. 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.

Cyclophosphamide-induced alterations of the micturition reflex in a novel in situ urinary bladder model in the anesthetized rat

“…Namely, in the CYP‐treated rats, spontaneous contractions occurred for a longer period of time following stretch‐stimulation. In the rat, several studies have shown that both CYP‐induced cystitis and spinal cord transection can increase the spontaneous bladder activity, in particular during the filling phase . The origin of these spontaneously arisen contractions has been debated, but several studies have suggested the urothelium and/or sub‐urothelium to be involved .…”

Improved efficacy and in vivo cellular properties of human embryonic stem cell derivative in a preclinical model of bladder pain syndrome

“…Cystometrograms were performed on unanesthetized and unrestrained rats in metabolic cages. Simultaneous catheterizations for intravesical pressure (IVP) and intra-abdominal pressure (IAP) recordings were performed 3 days prior to cystometrogram as described previously 55 , 56 . Briefly, following the induction of anesthesia, a polyethylene catheter (PE-50; Becton-Dickinson, Parsippany, NJ, USA) with a cuff was implanted into the dome of the bladder through an abdominal incision.…”

The Therapeutic Effect of Human Embryonic Stem Cell-Derived Multipotent Mesenchymal Stem Cells on Chemical-Induced Cystitis in Rats

“…Cystometrograms were obtained from unanesthetized unrestrained rats in metabolic cages. Catheterizations allowing measurement of intravesical pressure (IVP) and intra-abdominal pressure (IAP) were performed 3 days prior to cystometrography, as described previously [ 25 , 26 ]. The bladder was accessed using an inflatable PE-50 catheter (Clay Adams, Parsippany, NJ, USA) connected to a pressure transducer (Research Grade Blood Pressure Transducer, Harvard Apparatus, Holliston, MA, USA) and a microinjection pump (PHD22/2000 pump; Harvard Apparatus).…”