MP28-13 URETHRAL AND DETRUSOR DYSFUNCTION ARE DETERMINED BY THE SEVERITY OF A CONTUSION-SCI IN FEMALE RATS

Abstract

You have accessJournal of UrologyBladder & Urethra: Anatomy, Physiology & Pharmacology I1 Apr 2016MP28-13 URETHRAL AND DETRUSOR DYSFUNCTION ARE DETERMINED BY THE SEVERITY OF A CONTUSION-SCI IN FEMALE RATS Timothy Boone, Carolina Rivera, and Alvaro Munoz Timothy BooneTimothy Boone More articles by this author , Carolina RiveraCarolina Rivera More articles by this author , and Alvaro MunozAlvaro Munoz More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.1063AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Rodent models for the study of neurogenic bladder dysfunction (NBD) after spinal cord injury (SCI) are difficult to standardize, mainly due to the reproducibility of partial cord transections, or the severity of a complete transection. The purpose of this study was to characterize the degree of NBD associated with a highly reproducible, contusion-induced, SCI in female rats METHODS We used an infinite horizon impactor to create a contusion SCI with a targeted magnitude of either 100 (102+/-0.75; 100kDy group) or 200 (204+/-1.5; 200kDy group) kDynes at the Th8/Th9 region of SD rats. Rats were video recorded to evaluate locomotion with the BBB scale that varies from 0 (no hind-leg movement) to 21 (normal function). After 4 weeks, cystometry (CMG) was performed via a suprapubic catheter in under urethane anesthesia. SCI severity was assessed by determining the presence of microglia, and MAP-2 expression. Data were analyzed with unpaired t-tests. Values represent mean+/-SEM and p<0.05 was significantly different RESULTS The BBB score at 3 days after SCI was 9.2+/-2.9 and 2.0+/-0.6, while at 4 weeks was 19.7+/-0.6 and 12.0+/-4.5 in the 100kDy and 200kDy groups, respectively. Microglia infiltrates the injury zone without affecting gray matter in the 100kDy group. Major tissue damage was observed in the other group. During CMG we saw increased intercontractile intervals in the 100kDy group, while 200kDy showed clear detrusor-sphincter dyssynergia with irregular voiding intervals and non-voiding contractions (NVC). We found a significantly high frequency of NVC in both SCI groups (23.4+/-6.9 in 100kDy, and 30.0+/-7.8 NVC/h in 200kDy). The duration of intraluminal pressure high frequency oscillations was increased (2.1+/-0.2s in intact, 4.9+/-0.7s in 100kDy, and 6.0+/-2.1s in the 200kDy rats). Micturition volume was significantly reduced in 200kDy SCI group (0.37+/-0.05ml in intact, 0.52+/-0.11ml in 100kDy, and 0.09+/-0.02ml in the 200kDy rats). The flow rate was significantly impaired in the 200kDy group (0.18+/-0.04ml/s in intact, 0.11+/-0.03ml/s in 100kDy, and 0.02+/-0.01ml/s in the 200kDy rats) CONCLUSIONS Our results suggest that a computer-controlled contusion SCI creates a reproducible urethral and bladder dysfunction that is proportional to the applied force. This NBD model simulates the human condition where traumatic SCI are more frequent, and results suggest that even minor changes in the microenvironment of the SCI region can affect bladder function © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e376 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Timothy Boone More articles by this author Carolina Rivera More articles by this author Alvaro Munoz More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...